HELP - cannot make a call & error message

view story

http://androidforums.com – Hi, For the last few days, sometimes a call disconnected in the middle of the call and for the next 15 sec I can't make a call and it says: "To place a call, please make sure Airplane mode is off and wait for network registration complete." every time I trying to call. After the 15 sec it says "Praparing SIM card..." and after that I can make calls again. Within those 15 sec - airplane mode is OFF for sure and it seems like there are a signal and cellular absorption (I mean there is no "X" on the cellular absorption sight on the top bar) Is there a problem with (General)