Less Material Delivered Against Invoice Paid

Bought 40 sqm of tiles and cement. Realised 5L Tile Bonds wasn't delivered instead a 1L. Called shops next morning 23rd to make them aware. Initially denied that i bought tile material from them even after telling them I've got invoice & contacts details from invoice on my hand. After long argument i suggested rather fax the invoice to him. Faxed invoice together with my cell number on it just incase. No one bothered to get back to me, I then called again and was made to hold for a very longtime as Philly was busy with another customer. He accepted & agree they made a mistake from dispatch. He will get back to me soon to advice with how they going to deliver. Nothing happened till close of business. Then called again next day 24/04/2015 @16:30 to check what's the latest. To my surprise Philly was very rude telling me how busy he is & hasn't got a car to deliver outstanding tile bond. It made me wonder if this was genuine mistake or its one of their ways of *****ing from customers. In his raised rude tone he asked me what i want him to do as he can't help me, \Told him