I can't re-create an account in OnDemand instance. How to reproduce.
1. Create a user.
2. Delete it.
3. Try to re-create it again with the same email address.
"There is already an account with the provided email address " error is displayed.
I believe this is wrong because the account has been deleted.
Don't ask me why I deleted the user instead of editing its details

I was just stupid.