Hi Ravishankar,
I understand how inconvenient it is when the detachable keyboard is not recognized at all.
Could you please confirm whether you’re using a standard Surface Pro Keyboard/Signature Keyboard or a Surface Pro Flex Keyboard? Also, do the Caps Lock or Fn indicator lights respond when the keyboard is attached and did the problem begin after an update, reset or physical impact?
If possible, please test another compatible Surface keyboard with your Surface Pro 9 or test the current keyboard on another compatible Surface. If another keyboard works, the original keyboard is likely the source of the problem. If neither keyboard is recognized, the Surface connector or device itself may need further inspection.
If Windows was recently reinstalled using a clean or custom image, please also install the correct Surface Pro 9 driver and firmware package, then restart the device.
Please let me know the results, especially whether the indicator lights respond and whether another keyboard is detected. Thank you so much for your understanding.
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