Nokia :: 5800 Doesn't Receiving SMS

i have nokia 5800, it doesnt receive sms after i use it for a week , then i have to replace it wid some other sim, doesn matter of same network or different, and then it starts workin fine.

when the problem persists, i turn it off and when i turn it on, i receive all the messages at once, even when network is not ready. after replacing wid some other sim and then putting back ma sim into ma cell, it starts workin fine again until a week goes and then again the same problem persists. i tried restoring factory settings , even resetted ma cell, but the same problem persists.