Switch Joy con shoulder button damaged

Hello, and thank you for taking your time here.

My friend has a Switch that we use to play in his house, recently the left shoulder button from his left joy con stoped working. We tried several options without actually oppening the joy con, mostly because im afraid of guarantees on the chance we need to take it to a repair store, but we have confirmed it really is only that button. However it is impossible for 2 people to play now, because the console does not recognize the press of the left shoulder button.

Anyone has had an equal or similar problem? If so, how did you fix it? Sould i just take it to the repair?

Thank you so much.

Sounds like someone has to take it apart and repair it, question is, can you?