After having issue reclaiming space after deleting and purging files and being informed that the storage has been successfully restored, I've downloaded and deleted literally everything in my account and the total is still showing "31.1 GB of 50.0 GB used".

Can someone please explain to me how I've deleted/removed/purged files in a way that I'm still using storage? I'd very much like to understand how to remove files correctly and in a way that will result in the reclamation of space.