How do I get my contact's photos to display full screen for incoming calls?

I've never added my contact on my computer, I've always done it through my phone (I didn't know you could do it through the computer). The problem is not the photo, it's that the call doesn't come in and take up the full screen. Now when a call comes in, it displays as a banner at the top of the phone where the time and date normally would be, so I don't notice anyone's phoning.

As far as I can recall, it's only started happening since yesterday after I used the new map app. I've checked my notifications settings and the phone settings and so far as I can see, everything is set the same way it always was. I checked my hubby's phone to see if it's maybe something new since this last update to IOS6, but the call displays full screen (regardless whether the contact has a photo associated to it or not) and not a banner at the top of the screen like mine.

I still don't know how to change this back. Any other suggestions?

I didn't think resetting all the settings was the best solution. I've modified a lot of settings on my phone and didn't want to have to firgure out how to get everything back to how I like them after the reset just to solve one small problem. In the end, I figured out it had to do with my Facebook app settings. When I was out and had a few minutes, I had logged into Facebook on my phone and it asked me to verify my info in order to log me in. I didn't realise it was also requesting my authorization to access my contacts. Once I changed the settings for my Facebook app, the issue corrected itself. No more missed calls!! 🙂

I went to "Settings" > "Facebook" > "Contacts" and clicked it to off. Everything has been back to normal since I made that simple change! Good luck! 🙂