Bug when dialer had no creds
# supporth
Hani Emoss
04/21/2026, 1:01 AMHey Vapi Support — my dialer ran out of credits which caused a burst of calls ending as silence-timed-out, and these were still charged (~$0.04 each).
Org: a85ae2ae-a0a1-403c-9c26-acd5aa72cf69
Assistant: 1d27b2b4-6470-48ea-91ee-1d87170eb1db
PhoneNumberId: 99e0bbf7-1ac4-44cd-b92c-7957f5424dde
Exact subset to refund: all calls with endedReason = silence-timed-out and createdAt in 2026-04-20T22:00:00Z → 2026-04-21T00:30:00Z (UTC).
Count: 471 calls.
Example call IDs:
019dad66-bf60-788f-af38-9e7db5292402, 019dad66-b6b6-7007-b203-173f3ec6c1ee, 019dad66-ae00-7003-8b8b-f8d15880cecd, 019dad66-a5c9-7007-b202-ddbb20fc657d, 019dad66-9cab-7003-8b8b-8e7f19473755
Happy to provide the full list of 471 call IDs on request.
v
Vapi Support Bot
04/21/2026, 1:01 AMThank you for sharing the details about the issue with your dialer running out of credits and the resulting calls that ended as silence-timed-out. Based on the information I have found, I am unable to provide specific details regarding refunds or internal processes for handling these calls. If you have any other questions or need further clarification, please let me know!
a
Adam
04/21/2026, 2:12 AMFrom what you described, this looks like a billing edge case tied to credit exhaustion + call handling logic (those silence-timeouts shouldn’t really be billed in bulk like that). I can help you:
Pull and verify the exact 471 calls
Cross-check logs (credits vs call lifecycle)
Prepare a clean refund request that Vapi will actually approve fast
Put a safeguard in place so this doesn’t happen again (auto-stop / alerting)
If you want, send over the full call list or give me API access/log export — I’ll handle it end-to-end.
@Hani Emoss
s
Shaunak
04/21/2026, 8:47 AMHi,
Thanks for the detailed report and for sharing the call IDs - we investigated all 471 calls thoroughly.
What happened:
Your Asterisk PBX (20.6.0) was establishing SIP connections to Vapi and the assistant was running correctly - but no live human was ever on the other end of these calls. Deepgram listened for ~38 seconds on every call and detected zero human speech. Vapi's silence timeout fired correctly at ~30s and ended each call as expected.
Shaunak
04/21/2026, 8:48 AMEvery call followed the same pattern: SIP connected, the assistant delivered its greeting, STT ran the full duration, silence timeout fired. The infrastructure worked as intended - the calls were simply being bridged to Vapi before verifying a live human had answered.
Shaunak
04/21/2026, 8:48 AMWhy a refund isn't applicable here:
The charges reflect real compute and service usage - STT ran the full ~38s on each call, the SIP connection was established, and the assistant was live. There's no platform error to refund against.
Shaunak
04/21/2026, 8:48 AMHow to prevent this going forward:
Enable Answering Machine Detection (AMD) on your Asterisk side before bridging to Vapi. This ensures calls are only handed off when a live human answers, not voicemail or dead air.
You can also reduce silenceTimeoutSeconds on your assistant to cut costs on any dead calls that do slip through.
h
Hani Emoss
04/21/2026, 6:41 PMthats because our dialer was out of creds cloud talk
Hani Emoss
04/21/2026, 6:43 PMwe use Asterisk to bridge cloud talk and vapi
Hani Emoss
04/21/2026, 6:45 PMi'd be happy to share the code and my conversation with cloud talk however if a refund is not possible thats perfectly okay as well it would just mean quite a lot to our organization as we are attempting a test for a prop dialer with vapi a part of the tech stack
Hani Emoss
04/22/2026, 7:59 PMany update ?
Hani Emoss
04/22/2026, 7:59 PM@User @User
s
Shaunak
04/27/2026, 6:23 AMHi Hani,
Thanks for the extra context. It confirms that the issue was caused by CloudTalk running out of credits, which resulted in "dead" calls being bridged to Vapi via Asterisk.
Shaunak
04/27/2026, 6:23 AMSince the SIP connection was successfully established from your side and Vapi’s infrastructure (AI and Transcription) ran for the full duration of those calls, we cannot issue a refund. The charges reflect actual compute time used by the assistant while it waited for a human to speak.
Shaunak
04/27/2026, 6:23 AMBecause the failure occurred upstream with your dialer and PBX setup, you’ll need to contact CloudTalk support or review your Asterisk configuration to ensure calls are only bridged to Vapi once a live answer is confirmed.
Shaunak
04/27/2026, 6:23 AMTo protect your balance in the future, we recommend reducing the silenceTimeoutSeconds in your Vapi assistant settings. This will ensure that if another "silent" call reaches us, the assistant hangs up much faster and minimizes the cost.