F&F not settled

Dear Team, I was working for a big MNC and was on probation period and after completion of 6 months was not confirmed. However I got another job offer and put in my resignation through email of 15 days instead of 7 days as mentioned in the offer letter. I have written "n" number of times to the MD as well as the senior manager but no reply. Its been over 2 years now and they do not want to reply back at all. In one of the emails I had mentioned to the senior manager that if not action is taken then will have to send a legal notice. To this the MD who was marked on the email too replied saying that I did not give handover and that's why no settlement. This is not true as my immediate subordinate was told to take handover but she refused to. I do not know how to go about this. Request you to please guide me on the same. I have all the emails with me and also the offer letter given by the company. My email address for communication is [deleted] and would request you to please not put this online.