Mac Bin won't empty: 'item in use' & undeletable folder

I cannot delete a folder in my Bin. I have made sure all permissions are Read&Write and that the folder isn't locked, there is nothing in the folder. When I tried selecting 'put back' it tells me: "user" doesn’t exist anymore. I think this is from when I transferred to my new mac mini. The folder is called SMNopCopierSandbox-E3F050CF-34CD-4158-9F74-4FD9F7A0F787

For more information, when I try two finger tapping on the Bin and selet 'Empty Bin' it shows a pop-up saying The operation can’t be completed because the item “com~apple~SafariShared~History” is in use. And continues to show multiple files in use even though they aren't showing in the Bin (files shown in order below):

“com~apple~SafariShared~History” is in use.

“TY59B5X35J~com~pleco~chinesesystem”

“com~apple~Keynote” is in use.

“com~apple~Pages” is in use.

“com~apple~Numbers” is in use.

“57T9237FN3~net~whatsapp~WhatsApp” is in use.

“iCloud~com~novosoft~TurboScanFree”

“iCloud~com~apple~passd”

“iCloud~com~facebook~Wilde”

“F6266T9T75~com~apple~iMovie”

“Mobile Documents”

“Library” is in use.

“SMNopCopierSandbox-E3F050CF-34CD-4158-9F74-4FD9F7A0F787” is in use.

I don't know what's going on. It isn't really an issue but it's just annoying and if I want to erase my Bin I have to go through each of these pop-ups every time.

If anyone knows what's going on/how to fix I'd appreciate it.