You may be staring at this error crossed eyed. Not to fear. We can rifle shoot this problem. Focus on the second line and notice any person's name. That name is an additional contact that is listed as a second primary contact. You should only have one primary contact.
Here is how to zero in on the culprit:
In the error locate the additional contact's name (e.g. Janet, Gilreath)
Copy and paste the full name or just the last name into the Kickserv search box
Click on Additional Contacts tab
Typically choose the second or bottom instance of this contact
Once in the customer record click on [Locations/contacts] tab
Off to the right you should notice 2 contacts listed as "Primary"
If they are the same contact listed twice, then you can delete one
Otherwise, you can click the edit button on either of these and uncheck the primary box to resolve the issue.