1
If the question mark key is only working with Sticky Keys enabled, that usually indicates the keyboard is not recognizing simultaneous key presses on that key.
In the Settings App, ensure the Filter Keys setting is disabled.
2
Open Command Prompt, then paste in this command and press Enter:
msdt.exe -id KeyboardDiagnostic
Run that Keyboard Troubleshooter to see if that can solve the problem.
3
If the problem is still not resolved:
Connect another external keyboard to your system, is that key working correctly on that keyboard?