Scrambled text on screen

Just assembled my PicoCalc-H but when trurning it on showed a whole lot of white lines and some boot message in white text which is illegible. There is no green text.

The screen has no obvious cracks or damage. I suspect the ribbon cable may not be in properly althought I have reinserted it a few times

Could you take some photos ?

I had also trouble with the ribbon cable. I felt sure it was in a couple of times. However the last time in went in just that bit extra. Be sure it’s very straight on so it goes in fully.