Nintendo Switch Lite L button squeaks?

Have now had a Switch Lite for about 2 weeks, now the L button squeaks when pressed? What should I do, the switch actually does not want to exchange because of the scores

Disassemble your switch (attention at your own risk) there are enough YouTube tutorials about that

Does this invalidate the guarantee and is there no easier solution?

If the Nintendo still has a guarantee, send the Nintendo Switch back to Nintendo or your seller and they should be able to help you.

That's exactly what I don't want to do because in the event that she complains, all my game data will be spilled

Then you just have to unscrew your Nintendo Switch, but it can be risky.