Bad quality of Ray ban sunglasses

Good day I bought a pair of ray ban sunglasses from Mat and May store about a year ago. The name plate on the frame has started to come off. This is unacceptable these sunglasses are supposed to be top range. I think the knock off last longer. I went to store on many occasions and emailled but no response on email. When i go to store the manager is nevet there and they take my number and details but never call me back.