Cannot add a domain to a new tenant since it seems to exist already in Office 365?

Thanks for all who responded.
I got the thing working.

I only had the hint of a******@tenantname.com for something called "Account Takeover"...
So I created aliases that made sense for me starting with "a"..

The 5th attempt was successful and I got an email with a link. From there it was simple. I got the login to a tenant that was called something like "tenantnamecom.onmcrosoft.com" with the login of email address removed for privacy reasons. As it turned out, someone started that process, but stopped in the middle. So the domain "tenantname.com" was kind of reserved for Office 365, but not actually finalized the setup.

After I finalized the setup, I changed the loginname of email address removed for privacy reasons to email address removed for privacy reasons, logged of, logged in again with the new name. Then removed the domain "tenantname.com" from that tenant "tenantnamecom".

After that, I was able to add tenantname.com to my own tenant.. The tenant "tenantnamecom" now sits around idling for itself until it will be probably removed by Microsoft.

I only assume that the whole thing was a leftover from the change of the VLA login procedures..


Perhaps those hints might help someone lese in the future.

Dan