Looks like the walls are interacting with another element such as a beam or slab or you have duplicated a wall into that location.
I would check the 3d view to see if there are walls in that location. Next switch all the layers on and see if there is a slab interacting with the walls.
If the other element has to remain where you have it then you can use a Layerset that sets the Layer priority to have a different layer number
AC versions 3.41 to 25 (UKI Full 5005).
Using AC25 5005 UKI FULL
Mac OSX 10.15.7 (19G2021) Mac Pro-2013 32gbRam AMD FirePro D500 3072 MB graphics