Hi Jerome Rutagarama,
Thank you for reaching Microsoft Community. We're sorry for the trouble this has caused you.
May I know if the keyboard language was set up to English(United States)?
The question mark is on the same key as the forward slash key. To create a question mark symbol, you have to press and hold down the Shift key while pressing the question mark key. Pressing the question mark key without the shift key will only create the forward slash symbol.
Kind regards,
Lavenia