Hello I activated the Vapi number but it doesn't work. I set up a form from Fillout on my website and also set up automating a call to the user from this form through Make using the Vapi assistant. But there is a problem that Vapi assistant is not calling due to an error. Here is the error text: An error occurred in this call: call.in-progress.error-sip-telephony-provider-failed-to-connect-call And this error also occurs when trying to “Callback” with Vapi. Based on the error description, I understand that the problem is in the Vapi number. Can you tell me what is the problem of not making a call and can you solve it? Thanks https://cdn.discordapp.com/attachments/1358757321857040515/1358757322062827640/1.png?ex=67f500de&is=67f3af5e&hm=12639a223945c742c915ed3a4924f175799e0e68d546f6b5178c6fd35cdcdf42&

Hi there! 👋 I understand you're having trouble with your Vapi number not making calls. I can't determine the exact cause of your specific issue without more diagnostic information, but I can definitely help explain what this error means and provide some troubleshooting steps. The error "call.in-progress.error-sip-telephony-provider-failed-to-connect-call" indicates that Vapi was unable to establish a connection with the SIP telephony provider while attempting to make a call. Here are some potential causes and troubleshooting steps: ## Potential Causes: 1. **SIP Configuration Issues**: - There might be a misconfiguration in the SIP trunk settings - The SIP URI might be incorrectly formatted - Authentication details might be incorrect 2. **Network Connectivity Issues**: - Your network might not allow traffic on the SIP protocol - Firewalls or NATs might be blocking SIP messages 3. **Telephony Provider Issues**: - The telephony provider might not be responding in the required time - There might be compatibility issues between Vapi and your telephony provider 4. **Geographic Restrictions**: - According to the [documentation](https://discord.com/channels/1211482211119796234/1211483291191083018/threads/1342942393267257475), Vapi numbers purchased from Vapi are generally restricted to making calls to US-based numbers only ## Troubleshooting Steps: 1. **Check SIP Configuration**: - Verify your SIP trunk settings in Vapi, including Credential ID, IP/Port, and Authentication details - Ensure SIP Register is enabled with the proper Domain and Realm 2. **Check Network Settings**: - Verify that your network allows traffic on the SIP protocol - Ensure firewalls/NATs are configured to allow SIP messages 3. **Check Logs**: - Review any logs or error messages from your SIP server for additional clues 4. **Verify Number Activation**:

Hey! To help track down this issue, could you share: - The call ID This would really help us figure out what went wrong!

bc5950b8-7e20-4c94-8128-293eebbccd2c

looking into it.