使用JavaScript在parse.com中的某个类中设置和保存指针

I am trying to create two pointers to store in a class called appointments. One pointer is for a teacher & other for the student. I have used a global variable for selectedTeacherId in another event to store the selected teachers user id as a string. below is my code. I get an error message 400 bad request. Why isn't my pointers & class saving?I am trying to create two pointers to store in