Pool lights not working had to drive back twice

I bought a colour changing pool light when I want to install it, it's not working we took it back to the Leroys on Hendrik Potgieter road little falls, when we got there, I was asked if I installed it correctly? I work on pools for a living so seriously, they have changed the light but when we got home AGAIN the light is not working, we asked if they can test it before we leave but was told they can't test products and also some of the parts was missing, all the boxes was open, do they not check if everything is inside? now we have to take it back again this is a 40 mnute drive from my house to there and we have to do this trip 3 times because you sell broken stuff to the customers, the blue light i have in at the moment is working perfectly and i have pictures to show how i tested and connected the lights your lights that is broken and my old light that is working seriously you need to get something in place to test your products, and If you give me ANY *****se when I take it back for the second time there is going to be trouble because this driving up and down is costing me money and then insutling me by asking if I know how to install it SERIOUSLY!!!