Chosen Solution
I replaced my battery using the ifixit tool kit and tutorial. All went well until I turned it back on. I was greeted with a black strip covering about a quarter of the screen along with flickering. I undid everything and checked the connections and they seemed to be ok. Put it back together and still had the same problem. Please help.
Walter Nasdeo if it is not the flex cable (check for tears etc. on it) and if it is not the connector than you must consider that this is a broken display. Samsung Galaxy Tab S7 Plus Screen Replacement - iFixit Repair Guide
Can you try with the old screen how it works? If everything is ok, the problem is definitely in the screen.
