Several people have reported problems regarding phone numbers not displaying correctly on iPhone 4S. The first issue is that phone numbers are not displaying properly; meaning that phone numbers are displayed as 3125551212 instead of (312) 555-1212. The second issue was that call lists do not show the associated contact name even though the numbers are in the address book.
This seems to only affect Verizon devices. To fix this problem, dial *228 (this is Verizon’s over-the-air programming number). Press the “1″ key on your phone to program or activate your phone. Wait while Verizon updates your phone. When the call is completed, open the Task Manager and kill the Phone, Message, and Contacts Applications. This should fix this problem.