The ideal solution is to sort your materials, but this may not work if Graphic Overrides are in play.
The other options are to move the studs a tiny amount or use a custom profile with a tiny chamfer that won't impact on your dimensions.
Alternatively if it is a small one off job add the missing lines manually. Sometimes 3D modelling results aren't perfect and it is less trouble to fix the graphics with lines & fills rather than spend a lot of time getting something as simple as a missing line to display.
You can use the morph tool to add lines in 3D if you need them to show in other drawings. The downside is if you move the "columns" on plan the morph line may be forgotten.
Apple iMac Intel i9 / macOS Sonoma / AC27UKI (most recent builds.. if they work)