Undo mistakes. If you click the wrong wall, you can always undo. Move your mouse back to the hammer box, but don't click it. Move your mouse straight down, past the rectangle, until you reach the square with the arrow pointing to the right (sort of like this "->"). Then move your mouse one square to the left so that it's on the arrow pointing to the left ("<-" like that). Click the left pointing arrow to undo what you did. Click the arrow pointing right to redo it, in case you clicked undo one too many times.. No Trading / Selling of anything about The Sims Mobile Related Stuff, that includes In-App Purchase & The Sims Mobile Account. 4. You can't delete wall sections.. Hey, in this Sims 4 video you see How To Delete Walls, Floor, doors and how you can remove the ground! I hope this short tutorial can help you, if yes you .