Has my contract been violated?

I started at an alternative school in August of 2017. I was hired as a behavioral manager. I was promised orally that I would have the opportunity to pick up over time on the housing units for extra pay during my interview. That was never granted. During the course of the year I felt forced to take on a teaching role for 2-3 months. I was left in a room full of students that IEPs stated there should be more than 1 person in the room by myself. After months of false promises I was finally put in the appropriate role. I have been lied to all year and my contract States that I am a behavioral manager and need to hold the appropriate certifications in order to do my job. I do have a masters in education but I am not a certified teacher and did not sign up for this role. Now I feel as if they are cornering me again asking me to teach extended school year stating they have an abundance of behavioral managers. There is more to this story but I feel this covers the basics.