Incomplete Part orderd

I received a quote from Rashad( Renault the Glen) which I paid in full. I was advised that it will take 3 weeks for the part to be delivered to the branch. After 3 weeks I called to find out if the part was delivered only to find out the part has not been ordered. the person who assisted me this time around was Mr Kgabo who then took all the details including the POP and start the ordering process. After 3 days the part was delivered. I went to the store for collection. to my surprise the part was incomplete( a side mirror without a mirror cover and the glass just a mirror holder is what I received. I was very disappointed as this was a necessity I could not drive without a mirror. I was then quoted again for the outstanding parts which I felt I was not interested anymore... All I want now is my refund as I did not touch the part I have all supporting documents and have purchased the full mirror from different reliable supplier.I called the branch manager Patrick Swannepoel who the advised that I should have not taken the part and they are unable to give me a refund for unused part.