Father cheated Son money

Hello , my father resigned from his job at 56 and his every month salary was below 6,000 per month . I completed education & got job in 2000 and was asked take care of them. Trusting my father, i kept sending him money for 18 years assuming my father will rationally spend and do the savings in my name. Since they had no home, i invested in a home in Coimbatore taking loan. Now my Father saying he only bought that house but home is on my name because loan in my name I only replayed.. In total, i sent them more than 3.5 crores ( bought some properties in my name, now currently I have a bank transaction proof of 80 Lakhs should be mine ). my parents started spending for my Sister marriage and deposited in bank. When i asked my father to give me my money back, he is saying it is all his own earning. shocking news is now he saying I have to give him 15 L. Except my salary nothing major income to him. I am NRI for nearly 20 years and I don’t have just 2 lakhs in my saving . All are in my Father name . I have a bank statement as proof of sending all this 20 years I earned . Please advise how can i get my money back. Can I approach bank to get stay order of his bank account ? How can I freeze his account ? Any solution plz. Thanks