So I bought an iPhone 6 from a friend and was setting it up. I get to the Touch ID set up and get an error message. Did it about 3 or 4 times. No luck. So I skip the Touch ID set keep going. I finish the set up and ask if I want to update to 9.2.1. I click update and I keep getting an error message. Is there anything I can do to fix the update error and will replacing the home button fix the Touch ID ?