My friend is not returning my money what he has borrowed from me in the name of investment in stocks

One of my friend has borrowed around 8.35 lakhs from me with a promise of returns from stocks and my friend is totally into this kind of stock marketing business. Now, it's been around 11 months, my friend has not return any single profit share and like this till date the amount escalated to be around 22 lakhs. I don't have any kind of agreement with my friend. It was purely on trust as I know him already and I have transfered the money via bank transfer in 3 parts.. Rest all watsapp chats I am having... Whenever I am asking to return everything my friend is showing excuses. At last I have served a legal notice to him and in that also he is not replying properly and when I am making him understand that after 15 days of notice served period I will take legal steps, then my friend questioning me that am I threatening him and he is raising his voice over me saying that he will give mentall haraashment case... After receiving the legal notice my friend agreed to do settlement which he conveyed via. Watsapp text not by properly sending a reply to my lawyer against my legal notice Thereby, I need suggestion...in this regrd