Bad service

I am highly disappointed with the service I received from Hyundai. I went there looking for a car, filled out the necessary application even paid deposit. 21 days later still no assistance. I sent out emails and call but still nothing. To a point where I sent an email to request a refund on the amount I had paid for deposit but still nothing. How do we trust other dealership associated with them when as a customer you are not made a priority.