Horizontal lines on the screen after replacing the battery. Fixable?

I replaced the battery of my 2015 iPad Pro (A1652) following this video.

Everything is working great but the top 2cm of the screen are now broken and it’s only showing horizontal lines.

At first, not even the touchscreen was working but I fixed it by disconnecting and connecting it again.

That makes me think that maybe the lines on the screen could be a connection problem instead of a broken screen.

Can somebody with actual knowledge tell me if that is possible?

I was extra careful when I was detaching the screen (I even used a hair dryer) so I’m pretty sure that I did not break it… Although I’ll trust you if you tell me that I did haha.