To add a game code to your account, just follow these steps:

1. Log into your account and select "Add Premium Time".
2. Select "Single Payment" and click on "Continue".
3. Select "Game Code" as payment method and click on "Continue".
4. Select whether your game code is valid for 30 days. Enter the 20-digit code and click on "Continue".
5. Check if you have entered everything correctly. If you find all data to be correct, you need to accept the Extended Tibia Service Agreement and the Tibia Privacy Policy by checking the corresponding box. Finally, click on "Submit".
6. You will now receive a message whether you have entered the game code successfully or not. If everything was done correctly, the premium time will be added to your account immediately.