What do I do if my volume button is not responding?

I have an Oculus Quest 2 that has a broken volume button and i need help either opening it and finding a video to help me do it or sending it in.

Before you tell me to use the app the person i bought it off of said they cant help me and I don’t have access to the account that the device originally belonged too.

Can Anyone help me figure this out by pointing me in the right direction. Please message me or something lol.