Employer accepted my resignation

Sir I hav joined this comp as an asst manager sales & service on Oct 2016 . My main office is in hyderabad but I was posted in jamshedpur. Due to my manager behaviour n lack of co operation I resigned the comp on 29th march. 2017. Now when I approached them asking to accept my resignation and give my reliving letter and last month salary and expenses. I am getting no response from their end. I have mailed my resignation to MD my manager and HR of the comp. And after repeated approach I am not getting any response from their side. As the comp is in hyderabad where should I approach n going frm jamshedpur to hyderabad os nt viable for me financially. There is no office in jamshedpur. As it was a sales job I had to visit places . Please help. What can I do si that they can give me my dues and relieving letter.