If you really did knock it off then it will probably require an upper case replacement as these new keyboard are almost impossible to work on.
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If you really are sure you did knock it off, then it will probably require an upper case replacement as these new keyboard are almost impossible to work on.
I think it came loose while you were just typing on it.
If so, it is covered by Apple by this Service program:
https://www.apple.com/support/keyboard-service-program-for-macbook-and-macbook-pro/
If you really did knock it off then it will probably require an upper case replacement as these new keyboard are almost impossible to work on.