URGENT: Outbound call not being placed - telephony permission denied

Support Help
1

i have been using retell for a long time now, i have followed step by step guide on connecting my telynx number (usa toll free) - followed step by step guide and everytime i place an outbound call via retell it is showing as Telephony Permission Denied - im quite frankly disapointed since i have been using retell a lot for my clients. i have created a new account and checked all settings

2

The telephony_provider_permission_denied disconnection reason indicates that SIP trunk authentication failed.(1)(2)

For your Telnyx toll-free number connected via custom telephony, verify these configuration steps:

1. Check Your Elastic SIP Trunk Configuration

Ensure you’ve completed these steps in Telnyx:(3)

  • Created the elastic SIP trunk with proper termination settings for outbound(3)
  • Set up the termination SIP URI correctly(3)
  • Configured authentication either via IP whitelisting or username/password credentials(3)
  • Set up origination for inbound with Retell’s SIP server address: sip:sip.retellai.com(3)

2. Import the Number to Retell

After moving your toll-free number to the elastic SIP trunk in Telnyx, you need to import it to Retell.(3) Supply the termination SIP URI you set up in Telnyx.(3) If you configured auth via credentials, provide the username and password as well.(3)

3. Common Issues to Check

If outbound isn’t working:(3)

  • Check your Termination SIP URI for any spaces and remove them(3)
  • Use a localized termination URI near your region(3)
  • Verify your username and credentials are correct (the username is different from the friendly name)(3)

4. Review Call Detailed Logs

Check the call history and detailed log in your Retell dashboard.(1) It contains the disconnection reason, the SIP error code, and the error message.(1) In most cases, this would be enough to identify the root cause.(1)

If the configuration is not correct, delete the imported number and re-import.(1) If that does not solve it, please check with your telephony provider to see what’s the error on their side.(1)

For additional support:

3

Hello @Ansell

Use the custom header with Invite

X-Telnyx-Username : (username in Telnyx )

Please share a call id After you do this.