Digitizer replacement now screen is switching off when reseating?

I purchased a second hand Ipad mini 2 which needed the digitizer replaced, when I replaced it I damaged the LED screen taking it off, I then purchased a new LED screen & fitted it (it worked fine) but I had damaged the new digitizer flex cable so I needed to remove the new screen to get to the connectors & fit a second digitizer,.

But now when I try to seat the new screen it all goes well until pressure is put on it near the middle at the bottom of the screen, by the home button, I don't understand why. I don't think the screen is damaged as it has had little stress put on it when removing it and works fine until pressure is put on it, then to get it working again I have to unclip the battery & refit the connector again?

Any help greatly appreciated