Poor Quality Flops

I have bought the flip flops in the month of May in Canal Walk and within July the flop broke the right thong and I returned at Cavendish and was assisted with an exchange. The exchange broke on the same area, mind you I am working from home and wearing my flops at home while working and for walking to the shop and back. I again took the flops to Cavendish and they gave me a hard time and told them I no longer need this flop cause surely there is a Quality issue or a Manufacturer defect with the item cause it can't be happening for the second time within a space of 3 months and I am the problem. They did not allow me to add amount to get flops with better quality and insisted that I take the same item even though I have stated that I am not impressed with the product and if it is happening with me surely it is happening with other people as well and I was told because the item is still available in stock I need to take it. Same thing has happened with the same flops for the third time in the same place, thong has broke in the right foot. Kindly call off this product because it is such a waste of money and I regret buying this style to begin with.