one of the buttons on my keyboard graduay stopped working

If one key gradually worked less and less, that commonly points to debris under the key or a hardware failure.

Try these steps in order:

1. Clean the affected area.
   • Inspect the keyboard for foreign material or lodged debris.
   • Use compressed air to blow dust and debris from the surface and between the keys.
   • A gentle vacuum with a dusting brush can also help.
2. Check whether it is only that keyboard.
   • Connect another keyboard to the PC, or test the current keyboard on another PC if possible.
   • If the problem follows the keyboard, the keyboard likely needs replacement or service.
3. Check Windows updates.
   • Go to Start > Settings > Update & Security > Windows Update and check for updates.
   • Missing updates can affect special key behavior.
4. If this is a Surface keyboard or Type Cover, confirm whether it is a hardware issue.
   • Press Caps and Fn a couple of times and check whether the LED lights turn on and off.
   • If the LEDs do not turn on, the next step is to submit a service order.
5. If the key still repeats, drops input, or does not respond after cleaning, treat it as hardware failure.
   • For Surface Pro Keyboard or Type Cover, the recommended next step is to submit a service order.

• Troubleshoot Surface Pro Keyboard or Type Cover
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• Troubleshoot problems with your Surface mouse or keyboard