Welcome to Justanswer.com, my name is Dustin.I'm sorry to hear about the issue you are having, I will do my best to help you resolve it.
To get started, I need to know what type of computer you are using, a Windows XP, Vista, Windows 7, Windows 8, Windows 10 or a Mac.If its a Mac, please check the OSX version as follows, Click the apple sign at the top left of your screen, then click about this mac. And then where it says version, send that to me as a reply.
Also, its possible that the email you received was a phishing attempt to get your password ***** login details.
Or, it could be an error in the gmail system.. Whatever the problem is, we will fi gure it out through this session.
Google doesnt have a customer support number unless you are a paying google apps member with a service pin code.
However, you could try to call the last number they had listed, and see if they can help you
If they cannot help you, you would have to rely on the free forums to get help, or return here where I can do my best to help you.