i used to have 3G coverage at my house, but starting yesterday i got the "no sim installed" error message. i put the phone in airplane mode for a minute, took it off and i had my 3G back. well last night i got the "no sim installed" error message again. after trying airplane mode and resetting the network settings a few times, my phone finally recognized the sim, but now i only get EDGE coverage. anybody else with this issue or know what it is?