Solution 1:
Download the Logitech G-Hub: https://www.logitechg.com/innovation/g-hub.html
Solution 2:
Deactivate the "Steam Input Per-Game Setting"
1. Open your Steam Library and navigate to the Tourist Bus Simulator
2. Rightclick on the entry Tourist Bus Simulator -> Properties -> Controller
3. Set the "Overrice for Tourist Bus Simulator" to "Disable Steam Input"