While imported hierarchy i have 3 objects geting the same material??


So I’m a beginner at twinmotion and i have some understanding of the software minus this problem here where in another project it was happening the same thing while applying materials to objects.
I have three objects: one topographic, two stairs, and a third railing. Each was made as a separate object in Revit, but somehow, when it was imported, it came as all in one while having the hierarchy selected.
Has anyone had this issue and how did u overcome this problem?