iPhone 7 error 51

I have just bought a 128 Gig's iPhone 7 over eBay.

On seller's picture, the iPhone was working. In the comment, the seller stated that the screen is damaged and that the top part of the screen is unresponsive to touch.

When i received it, the low battery icon popped up (cause the seller was unable to turn it off due to faulty touch screen).

So i plugged it to charger. Then a bootloop started with Apple logo. I then tryed to restore the phone but error 4013 occurred.

I have left the phone plugged the whole afternoon to let it charge.

Later i tryed again and then the restoration goes a bit more further but ended with error 51. I have tryed with two mac: error 51 each time and error -1 on windows...

I have tryed to remove the full screen assembly and perform restoration but the result is the same.

Any idea ?

Thanks you !!

To close this Topic:

I have tryed to restore the iPhone with 3UTools. It ended with error -1 while flashing the baseband. So it seem's to be a baseband issue.

The seller accepted that i send back the phone to him.