Hi
I know how you feel because the same thing happens to me when I was doing a stainless steel series 1,the issue I had was the battery connector was torn a little bit and the display cable had a small amount or abrasion on it so it was one of the two
My advice here would be to get some isopropyl alcohol and clean the battery connector and the screen connector just in case there is some dirt that isn’t visible to the human eye
And I would also inspect all the cables for damage
If this doesn’t work give me a shout and il try and further assist you!
Hope all goes well
Thanks:-)