When I was asked about a recovery e-mail address for my Gmail account I added my yahoo account home e-mail address. This has become my primary (user name for my Gmail account & has locked up Google on my new phone, and my gmail account....can't open to get in and fix anything.  Afraid to delete old account since it is attached to my new phone. 
I changed my gmail primary account user name to my yahoo e-mail & nothing works
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