To pay Joining Bonus back to company even they fired me

Dear Sir, Request your help in relation to a case . I am a chartered accountant with more than 6 years of experience. I have joined a Start up company in Gurgaon region for position of Manager- Accounts & Fiannce. The company has provided me Job description and requirement during interview was quit diffrent from what I am performing from last 6 months. They have provided me majority of task realated to filing of documents for E- Bank realisation certificate (which I realised for past three years till date) while same can be performed by a B.Com and likewise other task as well. After completing my tennure of probation and after 2 months they want to leave the organisation either immediately and paying the Joining Bonus back to them as I have not completed wuth them(inspite of fact that they have kick me off and not that like I have left company) while in offer letter it was not mentioned that I need to pay back to them when they will relieve me. I have completed most of the quarterly objective assigned by management and same is even approved . further worked for approx 10-11 hours every wor The reason satated by company is ineffiecinecy while as per past experience and academics I am qualified CA, CS and CWA along with 6 Six Green Belt Certfied in my previous oraganisation - Honeywell (amongst Forbes 100 company in World) and 5 - star lean certified in Genpact for my client GE Capital (amongstForbes top 50 company in world). Company is has doubled its revenue in a year and provide good incentive to its employee in the first year. So, there is no case of financial crises here. According to me, it is just a case of inefficiency of my manager during company tax audit who wants to put same to management that it happened due to me. He is further screaming me that if I do not payback the company joining bonus of 1.5 lakh then they will give negative feedback to other company. I have immense pressure from my family as I am the only earning member and my child is still attending a school session. It will really helpful for mass of people and stop the bad culture prevalent in India. Regards, Rakshit