RESIGNATION AND CONTRACT CANCELLATION

It has been 11 months since I m working with my company and in the month of August my visa will be expired.So after that I don't want to continue my job  and I want to go home because my family has already fixed my marriage in the month of November. I submitted my resignation to hr dept. At that time hr manager told me to submit the letter to my workplace manager then only he can do something .As according to the instructions of hr i gave my letter to the manager.But the manager told me it's not needed and I can go home on whichever date I want.The manager called n told hr that I can go .The hr then told him to send me in his office.Accordingly I went to hr's office but surprisingly he put a condition that I have to pay   bd600 for 1 year  plus air ticket money which he had paid when I came here and then only I can go.I had an argument with hr regarding this .And I told him that I am going to talk with my Managing director. And one thing  there is the split in management system in our company.As per that now this hr doesnot belong to our management. I addressed my resignation to this hr because he was the one to bring me here ,at that time the hr was working with our management .I told whatever hr said to me to my manager .And the manager is saying that he will talk with our managing director and I assured me that I don't have to worry about this and told that I can go home.So what should I do ,please I need suggestions.