Cheque Bounce

Hi, My Name is Preeti Joshi, Please help me as per mentioned scenario; I am very harassed by someone who is the master to harass the innocent persons. Someday I received the call of the share market broker and is he guide me to buy the some shares in share market to earn extra income and next day he arrange the meeting with his boss on their office. I have zero experience in share markets, Just I do what-ever he suggest to me and I am buy the some shares of rupees 50,000 for starting. I start playing as he guide to me. To check the real time price of shares I used the application that he is suggest to me, and to buy/sell the shares I just call them on the mobile number which is given by him. Then after some days he call me and said to buy the XYZ shares to gain more profit, and I do as per his recommendation, But I loss 80,000 Rupees in one go. Now he said me to give the money of 80,000. As per above-mentioned concern, I discuss with my office friend who have the knowledge of Share market, he ask me about the account opening and document process to buy/sell the shares. But I can’t do any paper work while buy the shares, and later I know that the way from which I buy and sell the shares all the illegal (Some Dabba Trading or insiders trading), I just give him to self cheque of 50,000 as a security to the brokers when I start the Share market, without a cheque I am not doing any other kind of paper work, Not filling any account opening form, not sign any-where on single paper also not doing and online process to open the account. I loss because of his fake guidance and assurance, Now I am not able to deposit the 80,000 rupees to the share market brokers. When I know, all is this illegal and the broker are not buying or sell any shares behalf of me, then I stop the payment of cheque from bank, and registered the FIR for lost the cheque book, because he not give any answer to me. I denied him to pay the 80,000 because the brokers are not have any prove of buy and sell any share behalf of me. Also after some days I check the news regarding his fake/private stock exchange on Newspaper of the same brokers regarding all this activity by someone else. Now he is send me the legal notice through advocate, in which mentioned to take the legal action Because I stop the payment of cheque and not return the friendly loan, My cheque number and bank name is mention and give the warning to me to take the action as per 138 N.I act with 420 IPC. And also daily harassed me by telephonic. So this is the real story of my case, kindly suggest the suitable action plan so I save myself from any legal action.