Restore your phone!!!
You may be wondering by now, iTunes is not detecting my phone, How do I do that?
Answer:- Just disconnect your phone from the computer. keep Itunes open on the PC. While holding the home button of the iphone plug the phone back in. Itunes will pop a message stating it has detected a phone in recovery mode. just follow the on screen instruction then to restore your phone. If your issue is still not resolved only an Apple technician can help you