This step might require someone to help unclasping the plastic clips.

Turn the device so that the bottom is facing up.

In the bottom, unclip the three plastic clips circled in red.

On either side, unclip the plastic clip circled in red

Slide the black covering forwards to remove.

All five clips have to be unclasped for the covering to be removed.

Careful not to break the plastic clips when putting it back on.