Switch Joy Con how can I fix it?

I have had my Nintendo Switch for over 2 years and have this drift with both Joy Cons so they move by themselves. For example, the first thing I noticed about Pokemon. I don't know how to fix that. I've seen and tried tutorials but both are still broken. Since we don't have that much money, we can't buy new joy cons either. That's why I once read that Nintendo repaired it for free but I'm not sure because the Joy Cons no longer have a guarantee. I don't know what to do next I can't do anything on the switch anymore except to counteract if I want something.

There's a YouTube video from "Roxtendo" where he explains how to fix it. You have to buy contact spray and spray it in here:

Yes, I've already tried it, but it didn't work