Not getting leave for ca final exam

I'm ca final student and my principal is not allowing me leave of three months. he is only giving me two months leave for exams. I don't know what to do now. I'm very depressed please any let me know I should I do. I requested him a lot but he threatening me of not signing the articleship completion form. can IcaI help me in this case. anyone with any suggestions please help I'm very frustrated.