Inspiron 3793 Keyboard problem

Hello community,

my Inspiron 3793 is 2 years old and out of warranty.
It worked perfectly fine up until a few days ago, when the space key started to act weird - it only works when I hit it right in the middle, when hit on the left or right side it does nothing. Secondly, there is a new and unusual klicking sound when I hit the space key on the left side.
I lifted it carefully from the keypad and checked fpr anything broken or some dirt, but it looks perfectly OK.
Another small issue: sometimes the keyboard seems to react extremely slowly, i.e. I type let`s say 15 characters, which do not appear on the screen, like the system is stuck, and then suddenly they are there.

Unfortunately, the laptop is used almost exclusively for writing, so without a working space key and sometimes slow reaction time it is extremely unnerving and almost impossible to use.

Apparently, the top case (palm rest and keyboard) is not available as a spare part.
Any suggestions what else I could try to solve the problem?

Best regards and happy holidays
hadalan