HELP NEEDED!

all of the sudden my phone acted crazy today. freedez and lost all signal.. when rebooting it wrote something like "something is wrong with your sim-card"... however my simcard worked fine in my N8. I tried flashin, but the signalproblem is still there... when restarting an errormessage shows: """"There was an error. Can not connect to the network. Please contact a Nokia Care service shop"""..

Any suggestions?


PLEASE HELP!!