Havaianas Quality on the decline?

My last 3 pairs of Havaianas have broken the the toe strap. The little disk falls off. Havainas used to last years, why is the production so poor now?? My last pair were only 8 months old and I’d hardly worn them. I was walking in a mall when they broke and I immediately went into the store- wearing only one, and showed the tread still as new. The shop assistant said he could’t do anything without a receipt and couldn’t even offer me a discount on a new pair. Is the company doing something to solve the decline in quality? Should I ever buy another pair? Please advise, thanks.