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The sign in method you used doesn't match this account. 

I get this message every time I try to log into my onstar account. I'm able to log into my Chevrolet account and all of the buttons are in there to start and unlock the car and all of that, but I can't sign in to view my onstar plan. I've called, chatted, and emailed into onstar support and they said they mad some changes to my account and that it should be fixed, but it isn't. 

How do I get this to work?