MS support "unable to reach you loop" for locating only GA account.

For 5 day in a row I've received this response to my support case "I am writing this email in reference to case ID 2609070010000261. I was unable to reach you at your contact phone number provided. Please let me know the best time frame and phone number to call you back by replying to this email. "
I do not have any missed calls on my phone, I have provided an alternative number, I have stated what I'm looking for in the email response, I have tried calling the number in the email but get to a " provide an update online " and hung up prompt.


I have a tenant Ive paid for. I'm trying to attach a domain that is my mostly unique last name to it that I forgot I had on another tenant ( that wasn't paid for yet and has my first name last name) and I dont know the GA username on the tenant, I've tried every iteration I can think of for a username. 

I'd just love for a password reset email be sent from that tenant and I think I would get the email, reset it, release the domain, and move on. 
however I dont see that tenant's onmicrosoft url in any of my emails either if that's a possible secondary issue. 

If anyone has suggestions for getting into the tenant or getting something more than " unable to reach you" I'd greatly appreciate  it!