Hi, I'm Sandy and I look forward to help you today with the best answer possible.
I'm sorry about the issue.
I will work with you until it is fixed. This is a question and answer session. Please do not hesitate to reply back to me at the box given below. I appreciate your patience.
First of all, please signout/ogout of the existing gmail account first:
Click the link: http://mail.google.com/?logout
Now, choose sign in with different user account and try to login into your correct gmail acccount.
If you're not able to login, choose, "Need help" and then follow on screen steps to create a new password ***** this.
If you face any issue, please let me know. I will help you with additional steps.
Thank you, ***** *****