To remove a contact you must first go to the 'Contacts' section within the client record.
When you click on the contacts section, it displays the contacts below. Click here for more information about how to add contacts to a Client Record.
To remove a contact from a client there is a 'Remove' button at the very end of their record as you can see in the image below.
When you click 'Remove', a validation message appears. If you click 'Yes' the contact is removed and if you click 'No' the contact is not removed.