Trouble accessing ZLJ24 Control Panel Box

[chich]

Hi there! I need to access my ZLJ24 control panel but am having huge problems removing the cover of the control panel box. I have unscrewed the 4 screws (circled in red in the image) however the cover does not want to budge. Is there a trick to opening it? Are there any clips or latches I need to additionally unfasten? I have run my fingers all around and had a good look but can't seem to find anything else requiring unfastening. Am not sure if the installers applied any form of adhesive to the box lid. Any help is greatly appreciated!