Left my business at a loss - false advertising

Online I have purchased 6 x pack of 10 (60) units of airfreshners to be delivered 2-4 days. Firstly it was not delivered and upon inquiry was told early next week. I called 7 working days later and was told they will deliver by Friday as it just landed in Jhb. I decided to collect from the courier company as it was an urgent order for a client. Upon collection, they only delivered 6/60 units. When I inquired, they said supplier says its cost per unit( on their website it was a pack of 10). They said they can get the othered delivered but I need to cover the unit cost they got from their supplier. This is false advertising and they have left my company at a loss.......I will not be trusting Showspace with any orders. After emailing them requesting they cover the shortfall of their false/incorrect advertising, I have not yet heard from them