An administrator account for the site. Administrators have full permissions to the specific site.
Steps
Go to Users > Manage Users.
Search for the deleted user account.
You can use the Search textbox and dropdown at the top to search by a user account field, such as Username, Email, Display Name, Street, City, social media account, or Preferred Locale.
You can also filter the displayed accounts by clicking/tapping Deleted.
Click/Tap the back-arrow icon for the deleted user account to restore the account.