try cleaning the connecter
https://sustainablog.org/2015/10/10-headphone-repair-hacks/Oct 19, 2015 - For instance, here's a file for a
new jack cover. Reconnect a wire to the lead. If audio is only playing through
one side of your
headphones, then a
loose or disconnected wire is the culprit. Repair the
ear cushion. If the cushion wears out or comes off of your
headphones, don't worry-that's fixable! Replace the ...