Why do some keys on my laptop periodically stop working?

Question

Iron

Some keys on the laptop keyboard periodically stop working (always the same). If you disassemble the laptop, unhook the keyboard, and then put everything back together - the keys work. The loop is ok. What could it be? the tracks are apparently intact, because sometimes everything works, and the keyboard was not filled with 100% liquid.
Help please, with the on-screen keyboard it's terribly inconvenient ..
PS. Here are the broken keys: af;xcn,./ plus left alt.
the problem is definitely not in the OS, I check in ubuntu live mode

Answer 1

This is clearly not a software issue, but a hardware issue.

Answer 2

I put on the tracks / cable, the legs of the chip or the chip itself (most likely on the clave itself).
Actually option 2 - call, replace Claudia. The first option IMHO for enthusiasts and pros.