Some of these intersections can be tricky and some you may not be able to fix correctly but have you tried changing the reference edge to the opposite side for one to two of the walls or perhaps all off them to the centre position?
Cheers,
Gerald Hoffman
“The simplification of anything is always sensational” GKC
Archicad 4.55 - 27-6000 USA
2019 MacBook Pro-macOS 15.0 (64GB w/ AMD Radeon Pro 5600M GPU)