Refusal to give back my wedding ring.

My husband bought me a wedding ring in April 2023. In December 1 of the diamond stone fell off. I took it to NWJ Somerset Mall ***. The store assistance asked me to come back on 15 January 2024 as their repair centre has closed for holidays. I went back on the 16 January, booked the ring in for repairs. On the 10 February i received a phone call that my ring was ready for collection. I went to collect it on the 12 Feb, the shop managers Loranda and Waseena refused to give me a ring saying i need to pay R500.00 as the ring was out of warranty. This was never communicated to me before. When i booked the ring in, i was never told that i must pay. When i received a phone call, i was never told that i must bring money. Only when i get to the store, i get a surprise. Even on their booking receipt there is nothing that that’s written about paying. I was only told yesterday that their guarantee is 6 months. I was not aware of that and they never communicated that to me. The ring was bought online. Could you help me to get my ring back please.