Poor quality

I visited Checkers Gateway on the 1st of November, browsed around for a blender and was told that the Platinum blender was a hot seller for over 2 years and almost no come backs. I initially was taking a bigger blender but the guy told me this one was better because of the 2 cups and little cleaning etc. I used this blender 4 times and it stopped working. I live in Fourways and went on Friday to Return it to the Pineslopes checkers. I told the lady that i wasnt to exchange it for another, they refunded me due to not paying attention. Eventually i was told to go back into the store and look for the item, to which i refused, i was then told they are out of stock and i must go to Leaping frog or Fourways mall. The lady then told me that she will check with Rivonia as she passes there daily and let me know, that was Friday i am still waiting for this call. I use this blended for gym purposes. Is this customer service that i should wait this long for something that is not my fault? if there wasnt a replacement why was i not upgraded or given the next available one? stores like Game do this, surely Checkers being such a large store would do the same? you guys suck when it comes to service not only your products but your staff as well.