never blow on anything with ur mouth, too much moisture can hurt parts. they have a setting in the option under controllers for calibrating the sticks and even motion controls id try that amybe u can calibrate them to ur liking.
I had two differnt left joy cons get "sticky" where they would continue to register the direction a pushed after letting go. Sent both to Nintendo for repair under waranty.
I didn't need a receipt, but my switch was still under warranty, you might need something like that if your joy con were bought seperate and your switch is out of waranty.
Wait for the controller to die, (You can do this by leaving a game on and taking it off the Switch, using the right joycon to play) and then charge it. Worked for a few people.