What to do the builders cheque bounced

I booked one flat in pre launch and paid 8.20 lakh as booking amount from Feb 2014 to june 2018 I paid this money by cash and received receipts containing rate, area, address etc.The builder told me start the work by September but he has not started yet and also not giving any dates.I told to refund but he is not giving back money.There was no agreement prepared. Only I paid amount and received receipts. so I cancelled my flat and demand full amount with intrest. Builder give me rs.8.20 lakh cheque and said I will give intrest after some days. But that cheque of rs.8.20 lakh is bounced. Builder said I will rtgs this amount in two days but he can not rtgs and not communicate with me his phone also switch off. He changed his resident house. What can I do