NU w/backup --- deleting entire backup

Trying to delete all backups from my online storage. Even in browser view, this has been an exceedingly slow & tedious endeavor ... perhaps impossible. Even after I purge a PC, it still shows as space used. My active PCs show no option for deleting. Surely there is a better way that Norton can handle this.

Can it be wiped clean server side and start anew?

Barring that, can I have my subscription [700+ days remaining] switched to NU ONLY? Very disappointed with the backup feature. If this is how it is going to be, I would prefer to use iDrive or another specialty software product.

Thank you for any assistance.