Take off the flash cover off and inspect the 2 U brackets that are under 1 L bracket. Make sure those 2 U brackets are level with each other. When you are testing this, make sure you put the flash cover back on or you risk the bulb coming out.
When doing this repair, don't forget about all the rubber grommets and stuff. Especially the one by the proximity sensor where the sensor sits. If you do not have this rubber piece, the screen will turn off during phone calls.