Legal notice by ex employer

Legal Notice for Criminal Breach of Trust and the Offences of Civil & Criminal Defamation as committed with an intention to defame the Social Reputation of our Client, Intentional Insult & Criminal Intimidation U/s 406, 504, 506, 499 & 500 of IPC , i have been served this notice by my ex-employer i)i had formally given resignation on 30/01/2016 and my resingnation was accepted on 31/01/2016 but this notice says i was given termination notice in december 2015 due do misbehave with one of my female colleuge which is false ii) they made me sign a decleration on 28/01/2015 stating aftere leaving this job i will not work in similar kind of job for next 3 years (i have joined similar kind of job) as i am good in my job and not working for 3 yrs in same field my carrier will be ruined iii) notice states that i have stolen thier datas and made them public which is false They are asking a compansation of 1 crore 50 lakhs for mental agony and 50 lakh for goodwill damage (my salery was 18000 pm) Notice has not stated that in how much time should i reply to it Please advice me should i reply notice or if i dont what can they do and will this suit stand in court of law The notice says it is without prejudice .what does it mean