Hi Richard, does the packaging/instructions state explicitly that its suitable for a Pi4?
This is I suspect a problem of buying the latest model before the peripherals market has caught up.
I could be wrong but i suspect its built pre pi4 and isnt suitable without taking a drastic possibly destructive approach. The Pi4 has a slightly different geometary to earlier models and a different top profile.
this ad google fed me seems to support my guess.
https://coolcomponents.co.uk/products/s ... 2aEALw_wcB
The display is secured into the case with four screws. A Raspberry 3, 3B+, 2, or A+ is then enclosed in the compartment on the back of the case.
You should be able to get a refund from the shop? and it shouldnt be too long before the market catches up with the new Pi
Or you could spend a bit of time measuring to confirm its not too destructive and attack the box with a hot knife or mini tool ...
edit - I dont mean to sound flippant, and if your having difficulty backstepping the physical install? post pics of the issue to enlist advice, lots of very handy folk in here..