Failing to repair my vehicle

Logan from F&S auto sold me a bmw 320 d F30 2013 model which he was aware the the mirror was damaged and it had some minor dents in the bodywork. F&S auto has been promising to pay for more than three weeks now so that I can take my vehicle for repairs buy they still haven't paid and it's a bit unfair becomes it's taking to long. They had asked for a quotation and I did give them a quotation but still they haven't paid me so that I can have my car fixed.