Agent asking 400 OMR fine for Cancellation of Visa in oman

Dear Friends,

                  I have working in muscat, Oman from march 2017. now i completed 9 moths. I working as a contract employee under one agent. my contract is for 2 years. for me no leave for 2 years. very low salary my client company give salary for position is 500 OMR. But my agent giving me only 150 OMR.

               I don't like this job. so i want resign my job and go to India. I tell my agent i am not like this job so please cancel my visa and send me India. he said if you want to cancel and go to India you have pay me 400 OMR fine to me.

                So help me my dear friends how i will go to India without paying 400 OMR to agent. Give me ideas as soon as possible.