How to replace light PCB on Electrolux refridgerator?

Hi everyone, I have Electrolux fridge, light of which has started flickering, so I decided I’m going to try to replace it. The model is LRC4DE35W and product number is 925070450-02.

Now, this model does not have the actual light bulb, but PCB containing three LEDs. I ordered replacement part but getting the cover off is difficult. See below how the backplate of the cover looks like. I tried to insert flathead into that small gap, twist it, but it’s in hard place (against back wall of fridge). I’m not sure if I understand how it’s supposed to come off. Any tips?

https://postimg.cc/gallery/J4k5Fcn