Did you return them to Costco? They have such a great return policy with no questions asked. You can just bring it back to Costco, even without a receipt. But you will need to bring both belts to get the refund. We had a crockpot we used for almost 2 years, and they took it back because the handle fell off. We didn’t need a receipt -they just checked our credit card and it has a history of all the purchases we ever made. We have also returned a Roomba after a year because it stopped charging… no problems at all. You should definitely take your belts back so they know that it is a poor quality product!