Thank you for creating your own post on this topic with all the details required to get started!
Deleting it is not something you can do yourself, as you can't access the account. The Forum Team can get it escalated to email provisioning when they reach this post.
They will send you a private message to get the email address and pass security, then raise a ticket. When they are done, run the address through mailtester.com to verify it is permanently deleted. If not, come back and try again.