> ## Documentation Index
> Fetch the complete documentation index at: https://documentation.uponai.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Debug Outbound Connection Issues

> Diagnose why outbound calls have a not_connected status.

When an outbound call has `not_connected` status, the call failed to reach the destination. The cause is tracked in the `disconnection_reason` field.

## Disconnection Reasons for Not Connected Calls

| Reason                                 | Description                                                                      |
| -------------------------------------- | -------------------------------------------------------------------------------- |
| `invalid_destination`                  | Destination number has spaces, invalid characters, or wrong format (check E.164) |
| `telephony_provider_permission_denied` | SIP trunk authentication failed                                                  |
| `telephony_provider_unavailable`       | Telephony provider is down or erroring                                           |
| `sip_routing_error`                    | SIP routing loop or misconfiguration                                             |
| `marked_as_spam`                       | Call blocked because the number is marked as spam                                |
| `user_declined`                        | User explicitly declined the call                                                |
| `dial_failed`                          | SIP error code unavailable or unknown error                                      |
| `dial_busy`                            | Number dialed is busy                                                            |
| `dial_no_answer`                       | Number dialed did not answer                                                     |

## Troubleshooting Steps

<Steps>
  <Step title="Check call history and detailed log">
    The log contains the disconnection reason, error message, and optionally a SIP error code. If a SIP error is present, check the PCAP file for details — see [Debug Calls with PCAP](/Reliability/debug/debug-calls-pcap).

    <Note>
      PCAP files are only available when the agent's data retention is set to **Everything** and SIP transport is **UDP/TCP**. TLS transport calls will not have a PCAP.
    </Note>
  </Step>

  <Step title="Dig deeper if logs are insufficient">
    **For custom telephony:**

    * Double-check your imported number configuration
    * If configuration is wrong, delete and re-import the number
    * If still failing, check with your telephony provider for their-side errors

    **For UponAI-purchased numbers:**

    * Ensure the destination number can accept calls (UponAI numbers currently call US numbers only)
  </Step>
</Steps>

## Number Marked as Spam

High outbound call volume spikes without warmup, or a low pickup rate, can cause carriers to mark your number as spam.

**Remediation options:**

* Purchase a new number and warm it up slowly before routing full traffic to it
* Increase your pickup rate — see [Increase Call Pickup Rate](/Deploy/call-pickup-rate/spam-likely)
* Register with the verified phone number feature — see [Verified Phone](/Deploy/call-pickup-rate/verified-phone)