My company is not relieving me.

I joined an MNC company almost 15 months back in March,2020. For most part of the first year, I was kept waiting for the training to begin. I was getting my salary although there wasn't any work for me and none of this is my fault. Every 2 weeks, I was told that the training would begin but it never did. I was always responsive to emails, calls or text from my managers in this entire period. After my training finished in March,2021(exactly by 1 year) and I was into production for 3 months, I realized the job wasn't for me. They were making us work extra hours and the pay seemed very less and it was taking a toll on my mental health as well. I decided to pursue my higher studies and put my resignation in the first week of June. It was accepted by my manager and they asked me to serve a legal notice period of 2 months. Meanwhile, I was trying to get my notice period reduced by using my annual leaves that I have accumulated over the time against my notice period. To which I was refused and got mocked that I was on paid leave for an entire year. Which was completely not my fault. In Fact I was given the wrong expectation and was made to wait throughout. I was told that my notice period would increase for how many days I take a leave. Towards the end of June, unfortunately I had a fall and broke my ankle bone and it got completely dislocated. I had to go through a surgery and I was advised by the doctor that I wouldn't be able to walk for 2-3 months. I have submitted all the documents such as discharge summary, X-rays, pictures stating why I cannot work even though it's work from home. I got a call from my manager after 2 weeks from the incident, stating that I have to be on unpaid leave for these 2-3 months and then come back to the office and work for the days that I have missed in my notice period which is another 40 days. My last working day as per my notice period is July 30. The manager is expecting me to wait for 2 more months and work for another 6 weeks which is not at all feasible for me. I have tried explaining my situation but he doesn't seem to listen. It feels like they are holding a grudge for getting paid the entire year(which is completely not my fault) and I had worked for only a quarter for the company. The HR doesn't even respond to either emails or calls or messages and they are purposely making the relieving process hard for people. I had noticed this happen for other individuals leaving the company. Seriously, what kind of company acts so rash when their employee is hurt. Is there any way I can take this up legally? I really need help in this regard.