If a user in your organization has left, you can unlink the user in the portal.
Log in to the portal.
Go to All Users.
Search for the person.
Click on View Profile.
Next to the organization name, you will find an X.
Click the X.
Answer the confirmation question.
If you select Yes, the user will be unlinked from your organization (the user will not be deleted).
Note: If possible, ask the user to change their email address and phone number to private contact details if the previously provided ones are linked to your organization.