Bad service for refund

i have placed an order with this company in May already and i was told the items will come in by the end of August and my client decided to cancel cause they cant wait for that long. however i am still waiting for my refund till date and everytime i am asking pc link of the progress they keep saying they are waiting for accounts and when we call call them they dont answer and also they take 5days before they can give you feedback. can someone please help with this issue because we are running a business as well. i dont know they are doing this because we are a black company or this is the way they treat their customers.