We provide customer support services through a cloud call center. From this call center, we can forward calls to our support number +902167065663 to our assistant on VAPI via SIP Trunk. When we forward the “Forwarding Phone Number” defined in the Assistant to another support line defined in the same cloud call center system with the phone number +90 216 706 06 24, we get the error message “Too many forwarding”. When we consulted the cloud call center, we were told that the problem is that the request sent via VAPI.AI is incorrect in this way, and at the same time, it is stated that this problem is experienced because it first comes with SIP Trunk and then comes with a direct call. It can be solved if routing with SIP Trunk again. This issue is very important for us. We share the relevant information below. We hope to find a solution as soon as possible. Account: kodiksdev@gmail.com Phone Number ID: f6508208-4800-4b81-8fb8-ff837a428db3 (adisyo test ai) Inbound Sip Url sip:+902167065663@sip.vapi.ai Assistant ID: 8dde19fa-ee99-4836-afe1-25c20bf222cd (TEST ARGE) Thank you, good work

@YavuzKomecoglu The problem you are describing is potentially both technical and regulatory. Where is the phone number coming from? Is that a Twilio phone number? a VAPI provided number?

Thanks for appreciating VAPI @YavuzKomecoglu > When we consulted the cloud call center, we were told that the problem is that the request sent via VAPI.AI is incorrect in this way, can you provide more details about VAPI doing incorrectly? Is call forwarding or REFER implemented incorrectly? Can you suggest PCAP files or documentation that I can refer to, understand, and reproduce? > and at the same time, it is stated that this problem is experienced because it first comes with SIP Trunk and then comes with a direct call. It can be solved if routing with SIP Trunk again. Please rephrase this and provide some documentation and data so I can try to reproduce it.

@YavuzKomecoglu DM me and I'll try to help you resolve this issue. SIP interconnect, specifically with existing legacy contact cenetes can be challenging.

Marking this ticket as Solved ✅