You are no longer able to connect personal Facebook Profiles to CoSchedule due to Facebook deprecating the permission that grants third-party applications access to publish posts to Facebook as the logged in user. You can review the information posted by Facebook for more details. Due to this change, you will not be able to connect personal Facebook Profiles to CoSchedule as of July 13, 2018.
Converting Your Facebook Personal Profile to a Facebook Page
In addition to CoSchedule continuing to support Facebook Pages, there are other benefits to converting your personal Facebook Profile to a Page.
Once you have converted your Facebook Profile to a Page you will need to connect the new Page to CoSchedule.