I don't know if you have solution for this already but incase you have downloaded an App from the AppExchange, Pardot App to be more specific and you have access to Salesforce engage as well, this is a result of adding fields in the Leads and Contacts Page Layout, so if you remove Marketing Action Summary Contact, Pardot Mobile List Membership, Pardot Mobile Activities, Pardot Mobile Social Data and Add to Pardot List you should be good. Just keep the mandatory fields namely: Pardot Activities, Pardot List Membership and Pardot Social.It worked for me.
Regards,
Osama Ahmad