If you don’t have access to the email address associated with your Spotify account, you won’t be able to update it by following the steps in this support article unless you’re already logged in to your Spotify account page.
I recommend getting in touch with Customer Support using this anonymous contact form; they’ll take a look and do their best to help. Make sure that you are logged out of any Spotify account in your browser when using the anonymous contact form, so that the username and custom email fields will show up; that way, you can enter the information for the account that you're having trouble with.
Alternatively, if you prefer support via Twitter, you can tweet @SpotifyCares.
I hope this helps, and let me know if you have any other questions.
Have a good day!
TreyAnastasioRock Star 3
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