Unprofessional and unacceptable customer service : Goldwagen, Bellville

Ordered a part, after one week after not hearing from them, I travelled from Green Point to Bellville branch - only to be informed that they had not received the part, and also failed to contact me (despite having my mobile number) 8 days after my first visit i receive a whatapp stating that although the parts cost R520, which I was forced to pay in order for them to order it, the courier cost is R580.60! Ridiculous - when I request a refund, they state that they are unable to do this although they agreed that they have messed me around. On the quotation that I received it does not state that a refund is not allowed on this ordered part