Maybe then you could think of other issues causing your mobile to not work?
Did it stop working right after you turned off bring up on boot option?
Is there any data left in the card? Have you changed or tried changing APN?
Could you execute gsmctl -j and gsmctl -g commands and put the output here? Or is this device in remote?
If it's in remote - it would be easier to reset the device back to its factory default settings.