Can't access old account or change email address for Adobe Spark project

Hi community... hoping you can help since Adobe Support was not able to do anything.

I have an old Adobe Spark project with an old work account. I tried signing into it to edit the project and I got this message:

"The microsoft.com domain is now managed by Microsoft Corporation - (CSEO). Please enter a personal email address to continue using your account. None of the products or services will be affected by this change."

Except it wont let me change the email address. I tried a personal, my new work, an email address that has no tie to any adobe ID, a fake one..... nothing.

I keep getting the error "This email address is unavailable".