Arun Dev Builders — Refund outstanding

We booked a unit measuring 100 sq yd/ sq ft on 30 nov 2006 in Arun dev builders’ housing project at Haridwar. Despite so many follow ups with the company, we were unable to get our flat. Hence we applied for Cancellation of our Registraion on 12 Feb 2011, but till date even after numerous follow ups thru personal visit at their C R park office and contacting thru calls, our Refunds including interest are still not paid by Arun dev builder.
We sent a notice thru our advocate but no response from Arun Dev Builder so far.
Pls suggest further course of action