Public Sector Insurance Co. — owner not paying back lease amount

Address:

#437, 6th cross, Jayanagar 7th block West, 560082

We are staying in a lease house which is under construction in jayanagar 7th block. We paid the amount to the owner on april 2017 who promised to complete the house in few days but its been 3 years now and he has not completed the house. We are asking back the money but he is just pushing the dates and threatening us. We dont know how to proceed and whom to contact for this.