Welcome to the Atlassian Community!
Licences/subscriptions are not directly linked to an email address, they have a set of "technical contacts" and "billing contacts" (who can be the same single person, although I would always recommend having at least 2 billing contacts and all your admins should be technical)
Go to myatlassian.com and look at the licence/subscription section to see them. You'll only be able to do it if you are named as at least one of the contacts.
If you don't know who the contacts are, then you could ask Atlassian - raise a support request, giving them the SEN of your licence or URL of your Cloud system, and they'll be able to tell you who the billing and technical contacts are.