Bad service

I took my everyday glasses in as the one ***** had come out and my lens was loose. They fixed it but only lasted a week and the lens fell out again. When returning to the branch in Newcastle kzn where they so called fixed it a week ago, on asking why this happened they told me they did not have the right ***** the first time but forced it in to fit. My glasses are now back with them and I want them to be fully replaced, I have not heard back from them and its been 2 weeks now. The service at this branch is zero. I will be handing this matter over to my lawyers by Friday the 15th Feb. 2019.