Invisible slope in my game editor

Hey people. I have unfortunately run into a problem in my unreal game. Suddenly a massive invisible slope-like wall has appeared in my game. I have check the map for the possibility of it being another meshs’ collision box that simply gets in the way but nothing can be seen in the editor. The invisible slope is also massive and extends over the entire length of the map. Anyone who knows what the problem could be?

Thanks in advance :slight_smile:

(and sorry for the ■■■■ quality of the video)