Central Board Of Secondary Education [CBSE] — resigning from cbse school

Hi, i am working in a cbse school. In my school teachers are getting hardly 2 free periods in a week. As i have to take continuous class, i had throat infection. So i decided to resign from there. I gave my resignation letter after giving 1 month notice period. Now they are not allowing me to resign. They are telling silly reasons like they have printed my name in diary. I have give 1 lakh R.s as caution deposit at the time of joining. They said they will refund the money whenever i am leaving. Now they are refusing to give the money also. Please help me with the rules.