Supertech — cancellation & refund of builder buyer agreement papers

I have a flat in supertech basera project, & i have paid about 7.2 lakh of rupees to supertech but due to delay in construction & i have tried to cancel my flat but till 6 month has been gone & i did not found any refund even i have submitted my original buyer agreement & payment original receipt to supertech.
Now i want to retain my booking & since last one month i doing fallow up with supertech rep. To return my original papers to me but in same also they are delaying soo much