failure to refund and respond to customer complaints

i made a booking with them 50% deposit as required, when i cancelled the reservation i sent them an email and called it seemed they were not even aware of the booking. after providing them with proof of payment and stating i cancelled 20 days before my stay which means they must refund me fully they agreed. now they no longer taking my calls and have never responded to my emails, i am starting to believe the hotel does not exist its just a ****