Blackberry Pearl says " Sim Card Error"?

Question

My service provider is T-mobile but I have an AT&T blackberry pearl, I already unlocked it and everything and for a while it worked just fine, but randomly one day it starting saying " Sim Card Error" and " Insert a Sim Card" even when my sim card was already there, while saying these things it wont let me send or recieve any calls but I can still get into the phone. Please anyone help me because right now im without a phone.

Please and Thankyou.

-BBYCKES :D

Answer 1

Mine has been doing the same thing, and in places where I know I should have signal. I still have the AT&T Network though.

Answer 2

SIM card holder makes improper contact when ir dropped. Just remove and re-insert the SIM. I face this everytime handset drops.