Boss Auto Spares Maraisburg

Last year bought 2x Tail lights which they had to order. Paid for them both. I do expat work so after 3 months collected the tail lights. One was defective so I took it back and was told they will order it. When I returned for R&R, I went to collect it but they sold mine to somebody. So they had to order it again. In December they told me that they still don't have it, so they will reimburse me. Im the beginning of March I went back to get the reimbur*****t but was sent away,,, saying they busy investigating my situation. Two weeks later and still this situation is not resolved. What to do?