If you have purchased the Adobe CC directly, then primary admin can not be changed. However you can assign secondary admin by logging in to the admin console.
If you have purchased it from reseller then you have to contact Adobe Support who shall assist you in changing the primary admin.
If you want to change the name of any of the user or re assign the seat to someone else, then you have to log as primary admin to www.creative.adobe.com, revoke the invite by clicking on the cross sign in front of the e-mail & reassign the seat by sending invite to new user.
Thank you very much for your reply.
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