diff --git a/sessions/sessions.go b/sessions/sessions.go
index a626f61cc..45cbaa2ea 100644
--- a/sessions/sessions.go
+++ b/sessions/sessions.go
@@ -1335,6 +1335,8 @@ func (smg *SMGeneric) BiRPCV1InitiateSession(clnt rpcclient.RpcClientConnection,
 		}
 		if authUsage != time.Duration(-1) {
 			*maxUsage = authUsage.Seconds()
+		} else {
+			*maxUsage = smg.cgrCfg.SessionSCfg().MaxCallDuration.Seconds() // Force max since -1 is not supported by OpenSIPS 2.1
 		}
 	} else {
 		*maxUsage = minMaxUsage.Seconds()
diff --git a/utils/slice.go b/utils/slice.go
index b7f77e1ba..c15f75630 100644
--- a/utils/slice.go
+++ b/utils/slice.go
@@ -32,6 +32,18 @@ func IsSliceMember(ss []string, s string) bool {
 	return false
 }
 
+// SliceHasMember is a simpler mode to match inside a slice
+// useful to search in shared vars (no slice sort)
+func SliceHasMember(ss []string, s string) (has bool) {
+	for _, mbr := range ss {
+		if mbr == s {
+			has = true
+			break
+		}
+	}
+	return
+}
+
 func SliceWithoutMember(ss []string, s string) []string {
 	sort.Strings(ss)
 	if i := sort.SearchStrings(ss, s); i < len(ss) && ss[i] == s {