Cannot recreate a User account once deleted

I have 30 users. All working fine. 1 user has forgotten their password. We removed the user account. Then re-invited the user. User gets the invitation email, clicks the link, clicks Create Account, and upon finishing the form it says the User already exists.
It does not kick back to admin for confirmation.
Can I get some ideas on the solution?

I would ask how you went about this to delete the user account? Possibly this old thread will help

You may try to use the /admin interface to delete the user.

Removed from the Members tab, clicked the 3 vertical dots for additional menu options and ‘Remove’, i’ll look at the /admin interface

EDIT: That worked. Thanks for the solution. Cheers