S****** Belt Replacement

Bought a drive belt for a s******, showed sample. Was given one and told it will last even though cost R200. Put belt on with new rollers, and drove to work. After about 5mins driving at 40kmh to not over stress the new items, i started smelling burnt rubber. After about 5kms the belt broke, looked more like it melted. It cost me R150 to get the bike taken on a bakkie to my work. Now there are excuses from the guy who sold me the belt for a replacement to be brought to me all at their cost.