This is going to sound a bit pathetic, but could somebody consider uploading a Youtube (or better Bitchute or something) video of how to put the lid on this thing?
Are you using the old LCD or the new?
If they are identical, lock the LCD in the cover and then slowly try to align the LCD with he pins of the Pi. Once this is done gently push do that the 2 hooks lock. Lastly reconnect power from the circuit breaker