Hey, this usually happens when the original caller ID gets lost somewhere between Retell → Twilio → Bitrix. If Twilio is masking the number or rewriting the SIP headers, Bitrix won’t be able to match the call to a contact. You’ll want to check that Retell is sending the real ANI and that Twilio is passing headers like From and P-Asserted-Identity without replacing them. Also make sure your Twilio SIP trunk is configured to allow “original caller” passthrough. Quick question: are you sending the call into Bitrix via SIP trunking directly, or is it going through Twilio Voice first? @javier.asoto.u