Frustrated at Goldwagen

Dear Sir/Madam

On the 1st of August I purchased an intercooler pipe for my Golf 5, 1.9 Tdi from Goldwagon. I then took it to my machanic to have it fitted. Whilst driving on August 3rd, the car lost power, I stopped the car at a garage nearby and noticed the pipe came loose. The clip was not holding it firm. The next day on August 4th I called Goldwagon and spoke to Kavesh the sales rep that sold me the pipe, I had told him that the clips are not holding the pipe so he told me that the pipe is sold separately and does not come with clips and that I should call the vw agents and purchase from them. When I called Weisis VW in Durban they said that each pipe comes with its own clips so it’s a perfect fit so obviously it’s custom made. I called Kavesh back and said that I would like to return the now used pipe for a refund because it’s not working and howbeit they did not advise me better? So he said to bring it in and they will charge me a fee and refund me less 10%. My response was why must I pay the fee if I wasn’t advised better? So he said bring it in we will discuss with his manager. When I did take the pipe back, kavesh said the pipe was damaged and he can not refund. How can the pipe be returned in the same condition after being fitted and used for 2 days. How can he sell me a pipe without clips for the greed of a sale and how can I pay for his mistake?

Please advise and help me get my refund.