If you can go to a camera store or any store that sells this model, and has a display model out, you can try putting another (same) lens on your camera. If the problem still occurs, we know the issue is with the camera body sensors.
If it shows as connected with the new lens, we know that you will need to have the lens serviced or replaced.
Once you find out, repost your problem with more details, or consult with your local camera shop.
You can also call Nikon Tech Support at:
Nikon Technical Support
8AM - 2AM (Eastern)
7 days a week
1-800-Nikon-US
1-800-645-6687