So I have opened my joy con to see what is wrong with it. (problem was sr and sl buttons werent working and the lights didnt work as well) And I have found the problem but after reassembling it doesnt connect to the switch anymore when it isnt in the switch. And I dont know what I have done wrong because I have reassemble everything right. please let me know which part of the joy con I should check to see if I broke something.
Nevermind found the problem
battery wasnt in right. The antenna was in the way