travelinmybudget - Refused to give my refund for which service is not provided

I have booked my trip to maldives through travelinmybudget (travel agency) and they quoted a price on the date we asked and after agreeing we paid a booking amount of **k and later they changed my dates and price which were higher. so I said I can't go on this price and asked to refund my amount. but they refused to refund my money.