If the Wall is simple (no components), you can go to the "Wall Sides" page in Properties and set up a Brick material for you 3D wall. Once the walls are in place, you use the Door or Window tools to place them into a wall.
It would help if you could post a problem file. It's hard to tell where the trouble could be.
Designer, Deluxe, (Basic, Expert, Professional), Platinum
Windows 10 Pro (1909), 64-bit