@Vlad M.
It sounds like the disconnection issue you experienced was due to Vonage, which is the call management service you're using. This can happen for various reasons, such as network issues, configuration problems, or service outages on Vonage's end.
To address this, you may want to check the following:
1. Review your Vonage account settings to ensure everything is configured correctly.
2. Check for any service outages or known issues on the Vonage status page or support channels.
3. Ensure that your network connection is stable and meets the requirements for making voice calls through Vonage.
If everything on your end seems to be in order, and you're still experiencing issues, it would be best to reach out to Vonage support for further assistance. They can provide more detailed information on why the call was disconnected and help you resolve the issue.
If you need any more help or have additional questions, please let me know!