Do you want to update the email you use to access the Meraki dashboard to manage your organization?
I don't believe support will be able to help you with that; for this reason, it's always recommended to have more than one organization administrator.
https://documentation.meraki.com/General_Administration/Cross-Platform_Content/Global_Overview#:~:te....
I am not a Cisco Meraki employee. My suggestions are based on documentation of Meraki best practices and day-to-day experience.
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