Hello, this is likely due to a connection issue. If you have already tried clearing client cache, flushing DNS cache, then restarting your PC and router, the next step towards helping correct this error would be to try logging in while using a VPN, which will likely require trying most, if not all, of the available servers before being able to bypass the error, or contacting your ISP and see if they are able to notice any blocks or discrepancies from their end.