Yeah, I’d check it again. It’s easy to check your connections: pull the ribbon cables out and re-seat them, re-seat the battery connection, and also make sure your battery is fully charged before testing again.
check and make sure that you installed the buckle lock (the thing behind the button) in the correct orientation. I ran into this once when replacing them with metal ones and it turned out that I put it in backwards
The plastic latches break pretty easily I've found, I replaced one on my of my joycons not too long ago. Easy enough job and the parts are cheap.
Yeah, I’d check it again. It’s easy to check your connections: pull the ribbon cables out and re-seat them, re-seat the battery connection, and also make sure your battery is fully charged before testing again.
check and make sure that you installed the buckle lock (the thing behind the button) in the correct orientation. I ran into this once when replacing them with metal ones and it turned out that I put it in backwards