There is nothing they can do to stop you from leaving the company after the completion of your contract. Take out prints of your emails you have sent them regarding your plans to quit, Keep them safely at home. Write to them again just one month prior to your end of contract mentioning your previous emails of the notices you had given them. After your contract ends and they do not want to let you go, then go to the Human Rights Committee and lodge a petition. They will call the company. If after this they still do not listen, lodge a complaint with the Labor Office. They will definitely assist you. While lodging a complaint with the Labor Office, do mention in the form you need your End of Service Benefits. Lastly, don't be afraid if you are fighting for your rights. They cannot file a complaint against you as a missing person, You can tell that to the Labor Office if they do this.