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Hi <@1145576664366055464>, I'm getting Error transferring: number is not found or outbound trunk not valid when trying to transfer a call to a Canadian number +16472925326. Here's what I've set up:


Twilio Elastic SIP trunk with Canadian number +14375235601
Termination URI: retell-agent-trunk.pstn.twilio.com
Origination URI: sip:sip.retellai.com
Retell IP 18.98.16.120/30 whitelisted in Twilio ACL
Canada geo permissions enabled
Number imported into Retell via SIP trunking and assigned to agent
Transfer node set to SIP REFER, destination +16472925326 in E.164 format

Inbound calls work fine. Only the transfer fails. What am I missing?"

Call ID: call_57f37ec48285824aa81a56e9ba0

It looks like the transfer is failing at the trunk level, not the agent. With Twilio Elastic SIP trunks, SIP REFER transfers usually require outbound PSTN dialing to be allowed on the termination side. I’d double-check the trunk termination settings and make sure +1 numbers are permitted.

Also, is the transfer being routed back through Twilio or directly from Retell to the PSTN? <@1382766017326878772>