We have 6 years worth of archived files in the Deleted folder, and it comes up with a 'Cannot Delete Some Assets Permanently' error every time we try to delete any of them. This is taking up a huge amount of space in our plan! We need to clear the space but can't. It's not just one type of file, but all types.
Same issue and I opened a ticket. Crazy thing is if I am able to delete some of them, next time it syncs it puts them right back. There was an earlier thread on this problem, looks like going back to 2014. Back then support would delete for you if you opened a ticket, but seriously why is this problem not fixed yet?