Comfirmation and relieving letter not given by company

I had words with my client over the call and he was giving me few tips that how I can complete my new tasks thereafter, he was starting talking about his personal life and a very little talk about his company. After 4 days I have received a call from my another client and he was giving me heads up and telling me not to talk with him as he is telling everybody that I am sharing company’s information with them. So, On a same day I received a heads up call I contacted my manager and telling him everything. He was telling me that everything will be fine and it’s ok. Now, he had words with his seniors and they yelling on me and I said sorry for that. On the same day when my seniors were upset on me. My manager gave me 3 options and start harassing me and threatening me as they wanted me sign a bond for a complete year on a warning letter. The options he gave is :- 1. Sign a bond for year on warning letter 2. Terminate me 3. Or resignation I prefer resign as per the company norms but they were not ready to resign as per company’s norm as they wanted me to serve instant resign and they do promise that they will release my last month salary and send me the confirmation email on resignation. However, I have not received anything as of yet. I have contctd them many times and they are not replying and neither picking up my calls. My new organisation wanted all those docs until i cant join anywhere. Please suggest me some way to get my docs or Do I need to take some legal actions against this.