Hi there! This is a known issue with the OpenVPN licensing validation servers. There is currently no estimated resolution time, but the team is working on it, as I know. In the meantime, you can try restarting your servers or contacting support for more help. You might also find interesting how to pass salesforce AppExchange security. Here's a useful
salesforce security review. I hope it will help you improve your skills! Let me know if you encounter any difficulties! All the best!