Quest 2 issues

I have a quest 2. I hadn’t used in a couple of months. I went to play a game and it’s stuck in a never evens black screen. Left it overnight. Still nothing. 

did a reset. Now my app can’t find it. My device is listed but it won’t connect. Try to get support, apparently my serial number isn’t recognised. 

did a side load update, still nothing

reset the app. Still nothing

did another hard reset and sideload update

still it will not let me past the screen on the headset that says ‘continue in the app’ cos the app will not connect to the device. The device seems to have disappeared off my account online. But it’s still there in the app. 

HELPPPPPPP.