A GTempAccount is a conflicting account. This happens when a Google account is created using the same address as one which was previously used when signing up for another Google Service when the account was in use with a different email provider.
The password may or may not be the same as what you use on your current main Google account. To recover the temp account you will need to use the forgotten password workflow.
The steps below will guide you through the process of gaining access to the temp account and deleting it.
- Navigate to https://www.gmail.com/
- Type the GTempAccount (e.g. Usernamefirstname.lastname@example.org). Click Next.
- Since you may not know the password, just click on the Forgot password? link and follow the prompts to set a new password for the account.
- Log in to the account and navigate to https://myaccount.google.com/
- On the left-hand side of the page, click on Data & personalization.
- Select the option to Delete a service or your account. (You can delete the GTempAccount, but you will not be able to delete your main G Suite account.)
- Click on Delete your account, and follow the prompts to delete the GTempAccount.