Account disable for having VPN?

I recently got flagged for Terms of Use. They’re saying they disabled my account for use of a VPN, I havent been givng any explaination on what I did wrong when there isn’t anything mentioned in the Terms Of Use about use of a VPN. I only make local calls withing the U.S. and the VPN is intalled in my router. Ive had this Textnow account for about 4 years with no isssues and im waiting for that positive reply back telling me its an error on their end. Has anyone had similar issues and is their any suggestions on what i can do to get this fixed. Thanks in advance