Chosen Solution
I followed the iFixit guide to replace the screen. Initially the phone battery was fully drained. I removed the old broken display, connected the new one, charged the phone a little to test if the new screen is working and glued it. However, I didn’t to a good job with the glueing and decided to take the screen off and reglue it without disconnecting from the motherboard. I didn’t remove the battery either which was charged at about 20% at that point. Now the screen is black and I can’t see any apparent damage to the connector or pins.
you may have either 1 damaged the screen cables during the process of taking the screen off again, or 2 blown the display out because you didn’t disconnect the battery the 2nd time
