If your in the US, best advice it to just send it to Nintendo for a free repair. Thought I read before that this form of repair has the potential to damage the joycon, but could be wrong.
I sent bother of joycon to Nintendo last year for repair. No problems since, so far.
Brakleen can be used to clean electronics, so it's quite safe, basically any electronics cleaner should work. The fix I made was two months ago, and still works with no problems. They already were once fixed on warranty, worked without problems for 6-9 months.
The drift issue is caused by dirt inside the stick's electonic components, and the fix Nintendo does is that they clean it - atleast that's what they did to my joycons in 2019.