Calls not getting picked up by retell

Support Help
1

One of our customers was complaining that our agent is not picking up the calls, when we looked into his phone tree system I could find a log where it had 9 calls made from the same number to the agent during today and on retell it only shows me 6 calls from this number, I need more visibility into it

The 9 calls was made by the same number and to the same numbers that call call_a4b761b1b3ae13528aa6684a5c2, all of them between 10:58 and 11:58 EST today

2

@gio Hey, thanks for providing the details. Let me check this with the team, and I’ll get back to you with an update as soon as possible.

3

Hey Gio, what’s the inbound setup here, Twilio/SIP trunk into Retell or one of Retell’s native numbers?

If it’s Twilio or another carrier in front of Retell, the gap is probably there. Worth pulling their call logs for that number between 10:58 and 11:58 EST and checking how many calls actually got forwarded to Retell.
If their log also shows 9 going out but we only logged 6, that tells us calls are getting dropped or rejected on Retell end
If their log shows fewer than 9 reaching Retell in the first place, the gap is upstream and on the carrier side.

4

Hey @gio for each of the 9 attempts, could you share the timestamp (UTC if possible) and the SIP response code (or release cause) the phone tree recorded? If the tree itself sent INVITEs out, the carrier delivering them to Twilio should have egress CDRs we can correlate.

Thank You

5

Hey, unfortunately in this client we’re using twilio numbers from retell, not custom telephony so I cant see logs on twilio side, the phone tree just gave me a very poor log saying it the was missed, couldnt get any SIP logs with them, can you check on your telephony side? @Shah-Fazal

Timestamps are: 10:58. 11:02, 11:04, 11:05, 11:05, 11:06, 11:56, 11:58, 11:58

6

Hey @gio Checked Twilio, Only 3 inbound INVITEs reached us in that window — all 3 already show in Retell:

  • 10:59 EDT → +1XXX-XXX-3088 (call_a4b761b…)
  • 11:14 EDT → +1XXX-XXX-3364 (call_54e07959…)
  • 11:33 EDT → +1XXX-XXX-3364 (call_de1058fd…)

The other 6 timestamps reported (10:58, 11:02, 11:04, 11:05, 11:05, 11:06, 11:56, 11:58, 11:58) have no record on Twilio’s trunk at all — Retell never saw an INVITE, so there’s nothing for our system to “pick up.” Also note 2 of the 3 calls that did land were to +1XXX-XXX-3364, not the +1XXX-XXX-3088 DID the complaint focused on.
The break is upstream of Twilio — either the phone-tree’s outbound carrier dropped/never sent those legs, or the tree’s “missed call” log is counting internal retries/hops that didn’t egress as separate calls. The phone tree’s egress CDRs (release cause / SIP response) on its own carrier side will tell us which. If you can pull those, we can correlate; without them there’s no further visibility from our side.

Thank You