So on the Nintendo Switch, simply go to Settings / Controller Settings / and then activate "Pro Controller". That was it. However, I sent my controller back. The accuracy really leaves a lot to be desired. So even if it works, it's a shame to waste money.

To be honest, I have the same problem. I've tried everything, but it doesn't work. If anyone has a solution, it would be nice to know. Too bad about the money :-(