sony c902 camera keys not workng and low network coverage

hi, i have sony ericsson c902 and i reflashed it because it had low network coverage, and after reflashing phone's gdfs changed to k700, then i reflashed its gdfs and it agin and after that i just reflashed it with AS firmware and all was ok, but it still have low notwork coverage and now the camera keys on screen doesnt light up and doesnt work and also when you focus the camera then phone hangs for about 1 minute.

do anyone knows how to repair it?

It is hardware problem so take it to some repair shop.