### Answer --- This is a common issue with Twilio SIP trunking setup. Here are the key things to check: 1. Verify Termination URI Configuration Check your Termination SIP URI—if there's a space in it, remove it. You should also use a localized termination URI near your region. [(1) ]() 2. Check Credentials Make sure you entered the correct username and credentials. Note that the username is different from the "friendly name" shown in the credential list. 3. Ensure Outbound Agent is Bound Your phone number needs an

outbound_agent_id

configured to make outbound calls. If this is null, the number cannot initiate outbound calls without an agent ID override. [(2) ]() 4. Try Recreating the Trunk A community member reported success by deleting the trunk and redoing the entire setup process. [(3) ]() 5. For Canadian Numbers - Check Geographic Permissions Search "geo" in Twilio to find "Voice Geographic Permissions", select "Elastic SIP Trunking", and ensure Canada is enabled for outbound dialing. [(1) ]() If issues persist after checking these items, you may want to verify the number was properly imported to Retell with the correct termination URI and credentials.

​ To learn more, see the sources I considered: [[1] Twilio](https://docs.retellai.com/deploy/twilio) [[2] Get Phone Number](https://docs.retellai.com/api-references/get-phone-number) [[3] Twilio number not making Outbound calls](https://discord.com/channels/1186424376300679209/1362781970592960673) ​

Feel free to tag @AI Evy with additional questions. I also appreciate feedback, it helps me improve.