Tablet keyboard locked?

I've had a Huawei tablet with a keyboard for a while now. Yesterday I noticed that he no longer writes or does not react. And that although the Bluetoothverbindung worked. I also tried to reset everything and everything, but also does not seem to work. That happened to me a while ago and there was a key combination that I unfortunately forgot (I think something with Fn), but that's how it worked or the keyboard was unlocked - do you know how the combination is?

Try to install Swiftkey app, because Swiftkey can also fix problems with external keyboard. In my old Android Tablet I had problem with external keyboard that I could not write umlauts and that it has recognized ial English keyboard, with Swiftkey, the problem is resolved.

Thanks for the answer, but that's not the problem, it accidentally dropped some items on the keyboard (but not heavy or anything, so it's not broken or anything else), but somehow it hit some key so the keyboard was blocked, but I can't find out which: '/