Cannot perform SIP REFER on calls in Queue – How to transfer properly?

[diogo5121]

Hello everyone,

I’m running Asterisk (PJSIP) with calls entering a Queue(). When a call is in the queue, any attempt to send a SIP REFER results in:

503 Service Unavailable

same => n,Queue(support,Ttc,60,agi_natendida.py)

It seems that while the call is inside the Queue application, the channel cannot process a REFER, because Queue controls the channel internally.

What I’ve tried:

Sending SIP REFER from the agent endpoint → fails with 503
Redirect via dialplan → causes async goto errors

Questions:

1. Is it possible to perform a SIP REFER on calls that are already in a queue?

2. What is the recommended way to transfer answered calls from a queue without causing 503 or breaking the dialplan?

3. Should I use AMI Redirect, QueueRemove + Originate, or another approach?

[david551]

Please provide detailed logs, as if “perform a SIP REFER” means that the caller or callee sends REFER, it should terminate the application, even if it is Queue.

[cadillackid]

if the objective is to snatch a caller out of a queue and send them someplace else he could possibly use CHANNELREDIRECT .. I havent tried it as I have no need to do this but just a thought..