My friend is not returning my dues.

Hi, In 2019 one of my very good friend was planning start a bar and restaurant. He insisted me to pay him cash of around 2 lacs which i have paid him. Later on due to short of funds he and his wife insisted me to get a loan of 3 lacs from bank for them. Which i denied initially as i am a private employee. Later on they keep on requesting me through call whatsapp and personal meets to help them and they promised to pay the emi on time..I have helped them by getting loan from the bank. Initially one two months they paid the emi now they are coming up with excuses that they are unable to return the whole amount of around 6 lacs as their business is not operational. As he is a very good friend of mine looking into their emergency i didn't sign any legal agreement or didn't collect any cancelled cheque from now. Now they are not returning my money only giving me new date to repay my money. They have collected money from others also which are not paying back. I have all the whatsapp communication between us . Kindly guide.