how do I fix this error Warning: Missing argument 3 for App_Membership2::get_price() in /home/nwengl

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

After I updated from membership 1 to 2 I received the error above.
I also cant see my product page(subscription page) and I can seem to make an appointment. When I select the day then the time appears but when I select the time it just continues to what appears load.