Check the confirmation email from the store where you bought it (like Aerosoft or Steam).
If you’ve recently installed City Bus Simulator (whether it’s the classic 2010 title from Aerosoft, the City Bus Simulator Munich , or a newer indie version), you may have encountered a frustrating roadblock: a dialog box with the exact message: Check the confirmation email from the store where
If you encounter any issues during the activation process, here are some troubleshooting tips to help you: the City Bus Simulator Munich