diff --git a/agents/agentreq.go b/agents/agentreq.go
index aa7d6d8f7..326f7ffae 100644
--- a/agents/agentreq.go
+++ b/agents/agentreq.go
@@ -128,8 +128,6 @@ func (ar *AgentRequest) AsNavigableMap(tplFlds []*config.FCTemplate) (
 		} else if !pass {
 			continue
 		}
-		fmt.Println("==============================================")
-		fmt.Println(utils.ToJSON(tplFld))
 		out, err := ar.ParseField(tplFld)
 		if err != nil {
 			if err == utils.ErrNotFound {
@@ -167,8 +165,6 @@ func (ar *AgentRequest) AsNavigableMap(tplFlds []*config.FCTemplate) (
 		}
 		valSet = append(valSet, nMItm)
 		ar.CGRAReq.Set(fldPath, valSet, false, true)
-		fmt.Println("Set the value in nM")
-		fmt.Println(ar.CGRAReq.String())
 		if tplFld.Blocker { // useful in case of processing errors first
 			break
 		}
diff --git a/agents/diam_it_test.go b/agents/diam_it_test.go
index c485676a1..678ddc81a 100644
--- a/agents/diam_it_test.go
+++ b/agents/diam_it_test.go
@@ -51,15 +51,15 @@ var sTestsDiam = []func(t *testing.T){
 	testDiamItInitCfg,
 	testDiamItResetDataDb,
 	testDiamItResetStorDb,
-	// testDiamItStartEngine,
+	testDiamItStartEngine,
 	testDiamItConnectDiameterClient,
 	testDiamItApierRpcConn,
 	testDiamItTPFromFolder,
-	//testDiamItDryRun,
+	testDiamItDryRun,
 	testDiamItCCRInit,
-	// testDiamItCCRUpdate,
-	// testDiamItCCRTerminate,
-	//testDiamItCCRSMS,
+	testDiamItCCRUpdate,
+	testDiamItCCRTerminate,
+	testDiamItCCRSMS,
 	testDiamItKillEngine,
 }
 
diff --git a/data/conf/samples/diamagent/voice.json b/data/conf/samples/diamagent/voice.json
index 29ce1e7bd..5f5bd32de 100644
--- a/data/conf/samples/diamagent/voice.json
+++ b/data/conf/samples/diamagent/voice.json
@@ -19,19 +19,10 @@
 				{"tag": "Account", "field_id": "Account", "type": "*constant", "value": "*attributes"},
 				{"tag": "Destination", "field_id": "Destination", "type": "*composed", 
 					"value": "~*req.Service-Information.IN-Information.Real-Called-Number", "mandatory": true},
-
+				{"tag": "AnswerTime", "field_id": "AnswerTime", "type": "*composed", 
+					"value": "~*req.Event-Timestamp", "mandatory": true},
 				{"tag": "Usage", "field_id": "Usage", "type": "*composed", 
 					"value": "~*req.Requested-Service-Unit.CC-Time:s/(.*)/${1}s/", "mandatory": true},
-
-				{"tag": "AnswerTime", "field_id": "AnswerTime", "type": "*difference", 
-					"value": "~*req.Event-Timestamp;~*cgrareq.Usage", "mandatory": true},
-
-				// {"tag": "AnswerTime", "field_id": "AnswerTime", "type": "*composed", 
-				// 	"value": "~*req.Event-Timestamp", "mandatory": true},
-
-				// {"tag": "Usage", "field_id": "Usage", "type": "*composed", 
-				// 	"value": "~*req.Requested-Service-Unit.CC-Time:s/(.*)/${1}s/", "mandatory": true},
-
 				{"tag": "SubscriberID", "field_id": "SubscriberId", "type": "*composed", 
 					"value": "~*req.Subscription-Id.Subscription-Id-Data", "mandatory": true},
 			],
@@ -59,18 +50,10 @@
 				{"tag": "Account", "field_id": "Account", "type": "*constant", "value": "*attributes"},
 				{"tag": "Destination", "field_id": "Destination", "type": "*composed", 
 					"value": "~*req.Service-Information.IN-Information.Real-Called-Number", "mandatory": true},
-				// {"tag": "AnswerTime", "field_id": "AnswerTime", "type": "*composed", 
-				// 	"value": "~*req.Event-Timestamp", "mandatory": true},
-				// {"tag": "Usage", "field_id": "Usage", "type": "*composed", 
-				// 	"value": "~*req.Requested-Service-Unit.CC-Time:s/(.*)/${1}s/", "mandatory": true},
-
-				{"tag": "Usage", "field_id": "Usage", "type": "*cc_usage", "mandatory": true, 
-      				"value":  "~*req.CC-Request-Number;~*req.Used-Service-Unit.CC-Time:s/(.*)/${1}s/;30s"},
-
-				{"tag": "AnswerTime", "field_id": "AnswerTime", "type": "*difference", 
-					"value": "~*req.Event-Timestamp;~*cgreq.Usage", "mandatory": true},
-
-
+				{"tag": "AnswerTime", "field_id": "AnswerTime", "type": "*composed", 
+					"value": "~*req.Event-Timestamp", "mandatory": true},
+				{"tag": "Usage", "field_id": "Usage", "type": "*composed", 
+					"value": "~*req.Requested-Service-Unit.CC-Time:s/(.*)/${1}s/", "mandatory": true},
 				{"tag": "LastUsed", "field_id": "LastUsed", "type": "*composed", 
 					"value": "~*req.Used-Service-Unit.CC-Time:s/(.*)/${1}s/", "mandatory": true},
 				{"tag": "SubscriberID", "field_id": "SubscriberId", "type": "*composed", 
@@ -99,19 +82,10 @@
 				{"tag": "Account", "field_id": "Account", "type": "*constant", "value": "*attributes"},
 				{"tag": "Destination", "field_id": "Destination", "type": "*composed", 
 					"value": "~*req.Service-Information.IN-Information.Real-Called-Number", "mandatory": true},
-
-				// {"tag": "AnswerTime", "field_id": "AnswerTime", "type": "*composed", 
-				// 	"value": "~*req.Event-Timestamp", "mandatory": true},
-				// {"tag": "Usage", "field_id": "Usage", "type": "*cc_usage", "mandatory": true, 
-				// 	"value":  "~*req.CC-Request-Number;~*req.Used-Service-Unit.CC-Time:s/(.*)/${1}s/;5m"},
-
+				{"tag": "AnswerTime", "field_id": "AnswerTime", "type": "*composed", 
+					"value": "~*req.Event-Timestamp", "mandatory": true},
 				{"tag": "Usage", "field_id": "Usage", "type": "*cc_usage", "mandatory": true, 
-      				"value":  "~*req.CC-Request-Number;~*req.Used-Service-Unit.CC-Time:s/(.*)/${1}s/;30s"},
-
-				{"tag": "AnswerTime", "field_id": "AnswerTime", "type": "*difference", 
-					"value": "~*req.Event-Timestamp;~*cgreq.Usage", "mandatory": true},
-
-
+					"value":  "~*req.CC-Request-Number;~*req.Used-Service-Unit.CC-Time:s/(.*)/${1}s/;5m"},
 				{"tag": "LastUsed", "field_id": "LastUsed", "type": "*composed", 
 					"value": "~*req.Used-Service-Unit.CC-Time:s/(.*)/${1}s/", "mandatory": true},
 				{"tag": "SubscriberID", "field_id": "SubscriberId", "type": "*composed", 
diff --git a/utils/reflect.go b/utils/reflect.go
index 08ff41982..7a1d5a038 100644
--- a/utils/reflect.go
+++ b/utils/reflect.go
@@ -129,36 +129,35 @@ func IfaceAsTime(itm interface{}, timezone string) (t time.Time, err error) {
 }
 
 func IfaceAsDuration(itm interface{}) (d time.Duration, err error) {
-	switch itm.(type) {
+	switch it := itm.(type) {
 	case time.Duration:
-		return itm.(time.Duration), nil
+		return it, nil
 	case float64: // automatically hitting here also ints
-		return time.Duration(int64(itm.(float64))), nil
+		return time.Duration(int64(it)), nil
 	case int64:
-		return time.Duration(itm.(int64)), nil
+		return time.Duration(it), nil
 	case int:
-		return time.Duration(itm.(int)), nil
+		return time.Duration(it), nil
 	case string:
 		return ParseDurationWithNanosecs(itm.(string))
-
 	default:
-		err = fmt.Errorf("cannot convert field: %+v to time.Duration", itm)
+		err = fmt.Errorf("cannot convert field: %+v to time.Duration", it)
 	}
 	return
 }
 
 func IfaceAsInt64(itm interface{}) (i int64, err error) {
-	switch itm.(type) {
+	switch it := itm.(type) {
 	case int:
-		return int64(itm.(int)), nil
+		return int64(it), nil
 	case time.Duration:
-		return itm.(time.Duration).Nanoseconds(), nil
+		return it.Nanoseconds(), nil
 	case int64:
-		return itm.(int64), nil
+		return it, nil
 	case string:
-		return strconv.ParseInt(itm.(string), 10, 64)
+		return strconv.ParseInt(it, 10, 64)
 	default:
-		err = fmt.Errorf("cannot convert field: %+v to int", itm)
+		err = fmt.Errorf("cannot convert field: %+v to int", it)
 	}
 	return
 }
@@ -352,59 +351,56 @@ func Sum(items ...interface{}) (sum interface{}, err error) {
 		return nil, ErrNotEnoughParameters
 	}
 
-	// convert the type for first item
-	valItm := reflect.ValueOf(items[0])
-	switch valItm.Kind() {
-	case reflect.Float32:
-		items[0] = valItm.Float()
-		valItm = reflect.ValueOf(items[0])
-	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32:
-		items[0] = valItm.Int()
-		valItm = reflect.ValueOf(items[0])
-	}
-	typItem := reflect.TypeOf(items[0])
-
-	//populate sum with first item so we can add after
-	switch items[0].(type) {
-	case float64:
-		sum = valItm.Float()
-	case int64:
-		sum = valItm.Int()
+	switch dt := items[0].(type) {
 	case time.Duration:
-		tVal := items[0].(time.Duration)
-		sum = tVal
-	}
-
-	for _, item := range items[1:] {
-		valOtItm := reflect.ValueOf(item)
-		// convert to wider type so we can be compatible with StringToInterface function
-		switch valOtItm.Kind() {
-		case reflect.Float32:
-			item = valOtItm.Float()
-			valOtItm = reflect.ValueOf(item)
-		case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32:
-			item = valOtItm.Int()
-			valOtItm = reflect.ValueOf(item)
+		sum = dt
+		for _, item := range items[1:] {
+			if itmVal, err := IfaceAsDuration(item); err != nil {
+				return nil, err
+			} else {
+				sum = sum.(time.Duration) + itmVal
+			}
 		}
-		typOItem := reflect.TypeOf(item)
-		// check if the type for rest items is the same as first
-		if !typItem.Comparable() ||
-			!typOItem.Comparable() ||
-			typItem != typOItem {
-			return false, errors.New("incomparable")
+	case time.Time:
+		sum = dt
+		for _, item := range items[1:] {
+			if itmVal, err := IfaceAsDuration(item); err != nil {
+				return nil, err
+			} else {
+				sum = sum.(time.Time).Add(itmVal)
+			}
 		}
-
-		switch items[0].(type) {
-		case float64:
-			sum = reflect.ValueOf(sum).Float() + valOtItm.Float()
-		case int64:
-			sum = reflect.ValueOf(sum).Int() + valOtItm.Int()
-		case time.Duration:
-			tOVal := item.(time.Duration)
-			sum = sum.(time.Duration) + tOVal
-		default: // unsupported comparison
-			err = fmt.Errorf("unsupported comparison type: %v, kind: %v", typItem, typItem.Kind())
-			break
+	case float64:
+		sum = dt
+		for _, item := range items[1:] {
+			if itmVal, err := IfaceAsFloat64(item); err != nil {
+				return nil, err
+			} else {
+				sum = sum.(float64) + itmVal
+			}
+		}
+	case int64:
+		sum = dt
+		for _, item := range items[1:] {
+			if itmVal, err := IfaceAsInt64(item); err != nil {
+				return nil, err
+			} else {
+				sum = sum.(int64) + itmVal
+			}
+		}
+	case int:
+		// need explicit conversion for int
+		if firstItmVal, err := IfaceAsInt64(dt); err != nil {
+			return nil, err
+		} else {
+			sum = firstItmVal
+		}
+		for _, item := range items[1:] {
+			if itmVal, err := IfaceAsInt64(item); err != nil {
+				return nil, err
+			} else {
+				sum = sum.(int64) + itmVal
+			}
 		}
 	}
 	return
@@ -417,18 +413,16 @@ func Difference(items ...interface{}) (diff interface{}, err error) {
 	if len(items) < 2 {
 		return nil, ErrNotEnoughParameters
 	}
-
 	switch dt := items[0].(type) {
-	// case time.Duration:
-	// 	diff = dt
-	// 	for _, item := range items[1:] {
-	// 		if itmVal, err := IfaceAsDuration(item); err != nil {
-	// 			return nil, err
-	// 		} else {
-	// 			diff = diff.(time.Duration) - itmVal
-	// 		}
-	// 	}
-
+	case time.Duration:
+		diff = dt
+		for _, item := range items[1:] {
+			if itmVal, err := IfaceAsDuration(item); err != nil {
+				return nil, err
+			} else {
+				diff = diff.(time.Duration) - itmVal
+			}
+		}
 	case time.Time:
 		diff = dt
 		for _, item := range items[1:] {
@@ -438,7 +432,6 @@ func Difference(items ...interface{}) (diff interface{}, err error) {
 				diff = diff.(time.Time).Add(-itmVal)
 			}
 		}
-
 	case float64:
 		diff = dt
 		for _, item := range items[1:] {
@@ -448,18 +441,31 @@ func Difference(items ...interface{}) (diff interface{}, err error) {
 				diff = diff.(float64) - itmVal
 			}
 		}
-
-	// case int64:
-	// 	for _, item := range items[1:] {
-	// 		if itmVal, err := IfaceAsInt64(item); err != nil {
-	// 			return nil, err
-	// 		} else {
-	// 			diff = diff.(int64) - itmVal
-	// 		}
-	// 	}
+	case int64:
+		diff = dt
+		for _, item := range items[1:] {
+			if itmVal, err := IfaceAsInt64(item); err != nil {
+				return nil, err
+			} else {
+				diff = diff.(int64) - itmVal
+			}
+		}
+	case int:
+		// need explicit conversion for int
+		if firstItmVal, err := IfaceAsInt64(dt); err != nil {
+			return nil, err
+		} else {
+			diff = firstItmVal
+		}
+		for _, item := range items[1:] {
+			if itmVal, err := IfaceAsInt64(item); err != nil {
+				return nil, err
+			} else {
+				diff = diff.(int64) - itmVal
+			}
+		}
 	default: // unsupported comparison
 		return nil, fmt.Errorf("unsupported type")
 	}
-
 	return
 }
diff --git a/utils/reflect_test.go b/utils/reflect_test.go
index be6db3427..d4b4fecdb 100644
--- a/utils/reflect_test.go
+++ b/utils/reflect_test.go
@@ -466,7 +466,7 @@ func TestSum(t *testing.T) {
 	if _, err := Sum(1); err == nil || err != ErrNotEnoughParameters {
 		t.Error(err)
 	}
-	if _, err := Sum(1, 1.2, false); err == nil || err.Error() != "incomparable" {
+	if _, err := Sum(1, 1.2, false); err == nil || err.Error() != "cannot convert field: 1.2 to int" {
 		t.Error(err)
 	}
 	if sum, err := Sum(1.2, 1.2, 1.2, 1.2); err != nil {
@@ -558,14 +558,14 @@ func TestDifference(t *testing.T) {
 	if _, err := Difference(10); err == nil || err != ErrNotEnoughParameters {
 		t.Error(err)
 	}
-	if _, err := Difference(10, 1.2, false); err == nil || err.Error() != "unsupported type" {
+	if _, err := Difference(10, 1.2, false); err == nil || err.Error() != "cannot convert field: 1.2 to int" {
 		t.Error(err)
 	}
-	// if diff, err := Difference(12, 1, 2, 3); err != nil {
-	// 	t.Error(err)
-	// } else if diff != int64(6) {
-	// 	t.Errorf("Expecting: 6, received: %+v", diff)
-	// }
+	if diff, err := Difference(12, 1, 2, 3); err != nil {
+		t.Error(err)
+	} else if diff != int64(6) {
+		t.Errorf("Expecting: 6, received: %+v", diff)
+	}
 	if diff, err := Difference(8.0, 4.0, 2.0, -1.0); err != nil {
 		t.Error(err)
 	} else if diff != 3.0 {
@@ -577,18 +577,18 @@ func TestDifference(t *testing.T) {
 	} else if diff != 3.0 {
 		t.Errorf("Expecting: 3.0, received: %+v", diff)
 	}
-	// if diff, err := Difference(10*time.Second, 1*time.Second, 2*time.Second,
-	// 	4*time.Millisecond); err != nil {
-	// 	t.Error(err)
-	// } else if diff != int64(6996000000) {
-	// 	t.Errorf("Expecting: 6.996ms, received: %+v", diff)
-	// }
-	// if diff, err := Difference(time.Duration(2*time.Second),
-	// 	time.Duration(10*time.Millisecond)); err != nil {
-	// 	t.Error(err)
-	// } else if diff != int64(1990000000) {
-	// 	t.Errorf("Expecting: 1.99s, received: %+v", diff)
-	// }
+	if diff, err := Difference(10*time.Second, 1*time.Second, 2*time.Second,
+		4*time.Millisecond); err != nil {
+		t.Error(err)
+	} else if diff != time.Duration(6*time.Second+996*time.Millisecond) {
+		t.Errorf("Expecting: 6.996ms, received: %+v", diff)
+	}
+	if diff, err := Difference(time.Duration(2*time.Second),
+		time.Duration(10*time.Millisecond)); err != nil {
+		t.Error(err)
+	} else if diff != time.Duration(1*time.Second+990*time.Millisecond) {
+		t.Errorf("Expecting: 1.99s, received: %+v", diff)
+	}
 
 	if diff, err := Difference(time.Date(2009, 11, 10, 23, 0, 0, 0, time.UTC),
 		time.Duration(10*time.Second)); err != nil {