controller issues

[POUGY]

So I've been trying to play Smash 64 for the last 45 minutes now and I just can't get my controller to work. It's wireless nintendo switch pro controller, and I tried plugging it in to see if that would work, but it didn't. Also, my controller config is set to plugged because if I had that turned off Smash would tell me I didn't have any controllers connected. When I did turn on plugged the game opened but my controller still wouldn't work I really just want to know what I'm doing wrong, so let me know! Thanks!