If the incorrect email address was typed when adding a new user to your portal, it means the user would not have received a welcome email and would not have been able to set up a password.
Luckily, Content Admins and admins have the power to update a users email. This would be the fastest and easiest way to solve this problem.
Update a Users Email
One way to rectify this is to set the account associated with the incorrect email address to 'Blocked' in their profile settings, making the account inactive. Then, create a new account with the correct email address.
2. Blocking account.
3. Creating new user.
GO1 cannot change and save a user's email address without consent due to security reasons, so requesting to change the incorrect email on our end would require user email verification.