Sterling Holiday Resorts — Unethical behaviour

I had purchased Sterling Resorts timeshare 2 years back from Kochi office ( No.1218888) but had not availed it till date. I had paid Rs. 1, 95, 000/- for it. A few months back we decided to upgrade our timeshare to one in which we were able to use it in all seasons. The executive Sri Vibinkumar told us that the cost of the new one will be Rs.4.5 lakhs and since we had paid nearly 2 lakhs we need to pay only 2.5 lakhs. Since we were planning a trip to Singapore we readily agreed and paid Rs 1 lakh and agreed to pay the rest in EMI starting from 01/2017. But later came to know that singapore was not in their list of holidays we went by our own. Now they are telling us that the timeshare cost is Rs 6.5 lakhs and less the Rs 2 lakhs it is 4.5 lakhs we need to pay. But this was not mentioned to us at the time we paid for the share. The executive was not answering our calls as well. We would like a full refund of Rs 3.5 lakhs we had paid to the company. Our new Id is 1227615. Please help us get our money back since we feel we are cheated.