7 days return policy not explained

I went to the Spec Savers in Richards Bay on 25 April 2022 to collect my prescription glasses. I was in a hurry so I didn't really fit them properly. The following day I noticed that the frame was not sitting right on my face and I had to return them. I didn't get a chance to go back because I was so busy at work until Thursday the 05th May. When I got there I thought they would adjust the frame to fit my face only to be told that I have to choose a new frame and pay additional cash because I didn't return them within 7 days after collection. What I am unhappy about is the fact that no one explained to me that I only had 7 days to return the glasses should I encounter a problem. Now I have to pay R800 extra for a new frame. I find that very unfair!