Builder not ready to pay interest
I Purchase under construction property in Taloja Majkur Near Panvel City in Raigarh Dist. in 2017. I pay all the payment which necessary for Housing documentation approximately 3 Lakhs we pay to him, from last 2years i m paying EMI of mentioned property. The property is only 4 Floors and still he completed 3 floor in last 4 years and that 3 floors are not full furnished. Last sunday me and my Brother went to meet him regarding to cancel the agreement, because from last 3 years he tell us we completed in 6 months every 6 months he told us the same. in last sunday we request him for cancel this flat, because we need the house for living. he still told us plz wait for 6 months. in Dec 21 we will complete this project but i m not sure he will complete in next 6 months. I request him to cancel and repay our money with interest he refuse and not ready to pay interest.
Kindly suggest me what to do in next?, Can we claim for Money with interest? or could i wait for next 6 months.