Guys, the call transfer function is so broken for ...
# ❓・bug-reporte
Emanuel
01/06/2026, 10:53 PMI have done extensive testing
1) Warm transfer
I want the users id to appear as the caller. If i do this, warm transfer fails to transfer because it says i dont own the number so cant override. obviously I cannot use all my customers to receive the auth code from twilio to get that working. Cold transfer is able to pass the callers id instead of my agents id, helpful for the end staff member to just call back that person.
2) cold transfer
if i call the first possible transfer, and it fails, i need it to try someone else instead. but on cold transfer, if it fails on the first person, it just goes to voicemail and the call is over! Warm transfer is able to realise nobody picked up and try the next person.
3) unknown numbers
STILL having this issue and support is just asking me for more info, but its just a fact that the transfer function isn't able to pass an unknown caller number to transfer. if a callers number is hidden or they set to unknown, the tool just needs to fallback to agent number or something.
Emanuel
01/06/2026, 10:55 PMAgent ID: agent_127237f8755222384c0719bbe9
Agent Name: PlayFootball Outbound Lead Caller LIVE
Trunk: TK25154eb944331b2a96de5b3266a3ca33 (playfootball.pstn.twilio.com, IE1 region)
ISSUE 1: Warm Transfer - Caller ID Fails
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Retell Call ID: call_cd5e74d8232fc93d59017730aee
Twilio Call SID: CA189873af7b5cee69e43a4de6bdf51d22
Error: 32204 Invalid Caller ID
What happened: Transfer attempted with "User's Number" caller ID setting. Twilio rejected it because we don't own the caller's number.
ISSUE 2: Cold Transfer - Caller ID Works
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Retell Call ID: call_51342fd28d977dbbb051cce08b6
What happened: Transfer succeeded with "User's Number" caller ID setting. Recipient correctly saw the original caller's number.
ISSUE 3: Cold Transfer - No Fallback
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Retell Call ID: call_25767248c29477d768c5099107e
What happened: Primary transfer target didn't answer. Call went to voicemail and ended. Secondary transfer target was never attempted.
SUMMARY
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Same trunk, same agent, same "User's Number" caller ID setting.
- Cold transfer: Caller ID works, but no fallback if first person doesn't answer
- Warm transfer: Fallback works, but caller ID fails with error 32204
We need both: caller ID passthrough AND fallback capability.
Emanuel
01/06/2026, 10:55 PMWorkspace ID
org_7QOMDD7lTl1WjkGV