Drag and drop not working

I have just installed UIpath. with .net 4.7.1 While i am trying to drag and drop activity i am not able to do so I have restarted the system and uninstalled UIpath and reinstalled it. however I do not see any changes. While when I double click any activity i can see it in the designer place. When i click more activity those are created inside the activity. Would request help in solving this issue.

@sumankumar

Thanks