Incoming phone number not displaying

I just received my iPhone 6 last week and have had this problem since the very first call I've received. Whenever I receive a phone call, the caller's phone number doesn't show up on the call screen. Instead, I just get something like "WIRELESS CALLER" and then the state from which the call is originating underneath it. What's weird is that when I go into my recent calls and click the little "i" for more detailed information, the number is there -- but it is not displayed on the recent call screen itself.

I've spoken with Apple and Verizon about it and neither has been able to determine what's causing this to happen. Would appreciate any ideas.

Thanks.