Why does my character get blocked

cant progess further when walking to certain areas. I duplicated the bases of buildings from NeoCity Kit Bash (KB3D_Bldg_C_Base) to place under other buildings in my level but when walking around I cant walk onto the bases. What do you think the issue(s) could be? I dont want to earse them as they add visual appeal but my 3rdPerson Character does need to access these areas to get to the buildings that are placed ontop of the KitBash Bases UE5-0