Paid for service not rendered

I took my car to Renew It (Randburg) for repairs covered by the insurance and got the car back on Thursday (4 Feb 2016) after it has been there for three weeks for damage of R6 000. I asked them to fix two other minor dents for me; I paid them for both, but subsequently saw that the dents in the passenger door were not fixed. They are now avoiding me, not speaking to me when I phone. I am waiting for a guy called Eddie to phone me since Monday, when I phone back reception says everyone in management is busy with a client. All I want is my money back amounting to R1710 (VAT incl)