There are nothing called region locked in PRO, you maybe in the IP blocked or VNP issues. Also can be more detail about how you cannot log in? I assume that you login at the time it was full server in these past day. However, PRO server now is stable and not full.
What is your message when you click login client?
Once clicked login the game freezes FPS wise music keep going and once it unfreezes it says "Can not connect to server"; now again with a vpn i can instantly log in with no issues, and as your last post the conclusion is probably the ISP is blocking the connection.
But there is no reason for that to happen, even under the censoring rules it is mainly Gambling/pornography/Certain discrimnating websites/etc.
i can not understand why they would block but thank you for the help and its good to know it isnt from PRO end.