My phone is not turning on --error 56

Hello,

My iphone 7 is showing a screen that i should connect to itunes to restore, i connected to itunes to update to 11.0.03 ios update, at the end of the process when the apple logo is at the end , an error is occuring on the itunes on laptp that is error 56 , what is the exact problem? they tried tp put new IC NFC and nothing worked ! the phone is not turning on! they told me that there's a missing elastic behind the finger print and its cutten!

Please can someone help me to solve my problem, and in my country there's no apple store and here whenever the phone is opened no one would exchange it !

thank you