You may want to check which kernel you are using now which is giving you problems.I upgraded for 18.04 to 20.04 6 mos. ago & had many updates since but the last update caused my keyboard & touch pad to stop working.
According to the screenshot in #11 above it is
Code:
Linux 5.4.0-47-generic x86_64
If you reinstall and the older kernel works fine keep note of that and don't update the kernel to the newer version. Keep an eye on the Ubuntu Update Manager and examine the updates being offered. 'De-select' the newer kernel to avoid installing it.
It looks like you also have the
Code:
5.4.0-45
If that kernel worked well, ie. keyboard worked, etc., then update to that if wanted but no further.
P.S. This all assumes that a kernel update is the culprit. Possibly there is some other cause ¯\_(ツ)_/¯