Hi @awoobforknowledge,
I see. Try restarting your computer to see if you can release whatever it is that is holding that folder open.
Before doing any moving, make sure you are following the recommended steps for migration, here: How do I Move or Migrate files from one storage provider to another? - #2 by Tony so that you can ensure everything in that folder has been downloaded, before you move it.
After that, if you want to move the folder instead of copying it, make sure you don’t have any auto-trash rules set, so that the moved folder will be seen as a delete that goes into the trash queue. You can then restore it out of the trash so that it comes back as a placeholder file in Amazon.