Error for Appointments+ and Membership 2 Plugins

I just installed Appointments+ and Membership 2 and Im getting the below error on my "Make an Appointment" page.

Warning: Missing argument 3 for App_Membership2::get_price() in /home/ocmc/ocmedicare.com/wp-content/plugins/appointments/includes/class_app_membership2.php on line 89

Warning: Missing argument 3 for App_Membership2::get_price() in /home/ocmc/ocmedicare.com/wp-content/plugins/appointments/includes/class_app_membership2.php on line 89

Any thoughts?

Thanks,
William