has it been dropped? maybe lcd pooped itself or maybe display connector gone loose - if you have some experience pulling about things take it a part and have a look around to see anything out of the ordinary. if you are not confident best see your local repair shop. i personally love this devices even in 2019 alot of fun modding and running emulators which brings about nostalgic fun@! :)
Bummer, sorry to hear bud. Alot of courage poking around in a Macbook but unfortunately when these things happen its expensive lessons. Just the heads up though - did u thoroughy inspect the logic board whilst replacing keyboard to make sure no coffee spills were present?
take the battery out and see if it will fit then to ensure your battery doesnt have any swelling to be pushing screen up. I had a similar issue with 6s plus and my problem was solved when back camera shield was seated properly. Hope it helps.