Relieving letter and Experience Letter

I was working with a renowned IT company for period of 3 years based in Pune.I has requested for work from home option for period of 3 - 6 months a I was getting married and was going to return Pune after that. Inspite of many discussions with the manager , I wasnt given the decision on this and in month of February (i.e one month before my wedding) my work from home request was rejeccted. I had to forcefully resign as I did not have any options other than this.I had resigned in month of February and was informed to pay the compensation amount for the 2 months notice period.Due to my wedding expenditures I could not pay the amount that time. Its been 1 year & 5 months and Today when I am going back along with the whole compensation amount , the management is denying to give me relieving and experience letter.The reason they are saying is that I did not come back early and my case will be treated as Absconded case as per the company policy. I tried convincing my manger and top management , wrote many emails and tried many phone calls but they have rejected my request and are not changing their decision. What steps do I need to take in this case next?