The caller ID on my Blackberry curve 8520 always says unknown!

Everytime I receive a phone call from someone on my phonebook list it comes up unknown number. I have spent the whole afternoon trying to find someone to help me out but to no avail. This is getting extremely frustrating as I never know who is calling me. Please help!!!
Asked Apr 02, 2011
Try this:
Answered Apr 02, 2011
Do reverse phone lookup at to find out who is the owner of the number.
Answered Nov 21, 2022

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