If you gave account access to a site or app you no longer trust, you can remove its access to your Google Account. The site or app won’t be able to access any more info from your Google Account, but you may need to request that they delete the data they already have.
  1. Open the Apps with access to your account section of your Google Account. You might need to sign in.
  2. Choose the site or app you want to remove.
  3. Choose Remove Access.