iPhone 12 Pro Max - Blank screen after display replacement

Hello, I made a post a couple of months ago (link) and today I decided to replace the screen, however after doing so now it just powers on and stays like that, no apple logo or anything (there are some white lines on the right of the display). Does anyone know what could possibly be the reason?

https://preview.redd.it/kd1yqrv14zqd1.jpg?width=1530&format=pjpg&auto=webp&s=894ed1e24d0ee538334cd5caab2cf8663fc15885