Repairing L Button

Hello!

My mobapad M6 HD’s took a fall and now the L button won’t work. When clicked, it doesn’t make that click sound anymore either. I’ve never repaired or modded anything before so I’m clueless on how to fix it, but I really want to repair these as opposed to buying a new pair since I have the discontinued pink ones. Can anyone offer some help or point me in the right direction?