This problem is caused by incorrect login/passoword or internet connection issues.
We recommend to:
1. Check keyboard language. Check that Caps Lock is off. Read our password recovery guide article.
2. Check if firewall or antivirus blocks the game. Also, read the article.
3. Turn third-party programms off (such as torrent, Windows update, etc)
If the problem presists, please, contact our Support Team. They will help you with this issue.