NO refunds or exchange on resized rings, says Sterns Middelburg Mall, MP.

On the 11th March I bought rings for me and my partner. The rings did not fit and Sterns sent them for resizing. I was told that they will call me once the rings are back. Today I decide to go into the branch (Middelburg Mall, MP) to enquire. The rings are back and no one bothered to let me know. I then ask to exchange the rings, the lady says it is not possible because the rings are no longer in its original condition. What the ????. I did not even take the rings home, but now they say the rings are tampered with. Who tempered? It is their jeweller, not me. I would understand if the rings were resized by my own jeweller. This is not acceptable. I tried calling the branch manager but she did not answer. I am certainly taking this up with the head office, which I hope will be able to help. I need those rings exhanged, I don't like them anymore.