iPhone 7 Plus disabled

After doing an update on my phone the screen was black, I tapped the screen to see if it was done updating, this is when I saw the connect To iTunes, so my phone is totally useless , unusable. I followed the direction and put it on recovery mode, when it pops up in iTunes I hit update, then it does for about 15 min, I can see the progress bar on computer and my phone. When the bar is done on the computer , it’s only half done on the phone and then iTunes says “ the iPhone “iPhone” can not be updated or restored (-1) And we come to a standstill. This is brand new laptop we bought for 500 just to fix my phone( we needed a new one anyway, perfect time to get it) and I download the newest iTunes, the computer had been fully updated and it’s using windows 10 hone , restarted my computer. But it will not update or restore at all. How can Apple allow this to happen? This phone was 1100.00 and I am still paying it off. It will be 2 years in sept that I’ve had it. And If for some reason I do get help to fix it, I will lose everything on my phone. I saw tons of posts on this issue and no one had any real resolve. So where do I go from here?