phone stuck in the middle of a backup

my home button stopped censoring my figure print. The option doesn't show up in settings anymore either. It was suggested to me by a friend to back up my phone and then restore it. So I backed it up and then went to restore it and it got almost finished and stopped. I've called tech support and they said my MacBook Pro isn't "talking" to iTunes and that I should try it on a different PC. Did that... same thing.

How do I restore my phone iPhone 6 plus when it's stuck in the middle of a restore?