Hello there, and thank you for reaching out.
There can be issues with a VPN and how it communicates with your Sonic connection, though usually, this can be mitigated by setting it via the VPN or your router.
One option may be to reinstall the VPN client.
Some other options can also be resetting your network settings via your router, changing the VPN server location, checking for software updates to the VPN, and contacting the VPN provider support team for troubleshooting assistance. Your Sonic connection should not block any VPN connections.
If these options do not work, I would encourage you to test with the Sonic VPN service and see if this allows a secure connection. You can read more about the Sonic VPN service here https://help.sonic.com/hc/en-us/article ... PN-Service
Lastly, I looked at your account, and I see that you are using your own router, so there may be some settings that you can configure to allow the VPN connection.