Hi @Rich Thank you for reaching out to us, just wanted to check if you have followed the steps mentioned in this article - https://learn.microsoft.com/en-us/azure/active-directory/enterprise-users/directory-delete-howto
If the steps mentioned in the article doesn't help,send us an email on azcommunity [at] microsoft [dot] com referencing this issue with a subject line "ATTN:Givary". We can connect offline to troubleshoot the same.
Let me know if you have any further questions, feel free to post back.