The most likely issue is the layer intersection priority number for the layer combinations.
Can't really tell, as you don't tell us what "Show all" and "Foundation Plan" are ... are they layer combinations? Are they views, with layer combinations named something else? Is the foundation modeled with beams (appears so) vs walls? What version of Archicad are you using, and what country/localization? Operating system? Much of this can be put in your signature to populate this and future posts.
Assuming it is an intersection priority issue, most likely since the elements were likely all modeled with the same tool and layer... if the intersection priority is set to 0 (zero), beams and walls will not clean up with themselves. If non-zero, they will. So display each view in turn, checking the Layers dialog to see the intersection priority number for the relevent layer(s) in the view that works and the one that doesn't.
I'm guessing that there might be a different floor plan cut plane height and model view options between the two also.
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