Extremely bad service.

I have placed and paid for an order for 15x mecer mouse units on the 11th of July,that included a delivery fee. I have sent countless emails and called over 5 times. Last Friday night after much hustle the delivery company they use RTT delivered the wrong goods. I am self employed and rely on orders for a living. Today we are having a cold war. The courier service is dismissive,they can actually driver today but they are being a Goliath to a David n have dismissed me. I am loosing the order n need help. I am in the free state,Qwaqwa n I'm being considered on the outskirts. Initially they said they deliver on Mondays n baring in mind that today is the 12 th day after paying for the order I am still waiting.