Dues issues illegal termination

I work for a NGO registered as Society in Delhi since last 9 years. we started from 10 people & now having 300 people. Now last month they emailed me that you leave the current project on which i was working since last 6 years & you will be given big responsibility in organisation. I accepted on the same mail which was sent to management & my project team that i am happy to leave the project head so that new team can contribute with new vision, but that was a false call from management. after a week they called me & forcing to give resignation as organisation now cant afford you without giving proper reason. I told ok i will give resignation but i need some compensation which they told they will do but after resignation or else they will terminate me giving one month notice. they are refusing to provide gratuity saying we dont have this in process. I refused to resign and told that you terminate. what would be the best solution & implication of termination. is graduti implies on Society & ngos. are they bound to follow govt of india law against graduti act 1972? plz suggest thanks Devendra