Sometimes geometry in a 3D modeling program seems to be ok and then after importing it into Shapespark you can see some weird “shadows” that are changing while you move your camera. This problem can be visible even on simple geometry like walls - you can see some edges that shouldn't be visible and light doesn’t bake properly. Probably there is a problem with normals in your model. To fix it you have to go back to your 3D modeling program and check if the smoothing options are set properly. If not then delete incorrect smoothing and fix it by yourself or use auto smooth and check if it solves the problem.
Walls have smoothing - that’s why there are some weird artifacts.
Walls have hard edges - no smoothing - no artifacts