Suggestion in case left the company without any legal notice

Hi I left Reliance in 1 months 15 days without serving the notice period. I also handed over all the assets to the company. When I was about to join I was told that appraisal for next year wont be given and in lieu of that a one time bonus will be given. When I joined the company the Hr told me that the one time bonus will not be given now. I had health issues and i told the hr for transfer based on medical health checkup that was done before the employment by the company but they did not reply to that as well. I had relocated from my hometown to Mumbai and i was not given the relocation amount. I got a offer from my hometown and left the compnay without serving the notice period. Now i am getting recovery letters from the company to pay the company in lieu of not serving the 3 months notice period. I dont want to pay the heavy amount. Please suggest what i can do.