Why is my iPhone 7 boot looping after a screen replacement?

So a few days ago i bought a used iphone online. It had a cracked screen but worked just fine. I ordered a new screen and replaced it. After replacing it the problems started to happen. It would continuously boot loop.

I've tried to restore it using itunes several times. Sometimes it worked, but i couldn't get past the "hello" screen as the home button doesn't work anymore... I had to turn it back off in hopes it would start at language selection screen. Unfortunately, almost every time it shuts off it would go back into a boot loop. I've tried reconnecting the old screen too, but it's still boot looping.

I'm wondering if this is a software issue or if it's a hardware issue. If it is a hardware issue, is it the screen that sends it into a boot loop or can it be due to something else?

Any help would be much appreciated!