Diamond of ring keeps on falling out

My fiancé purchased my engagement ring from Sterns Greenstone in the middle of 2013. We got engaged 27 December 2013. Beginning 2014 (Jan / Feb) the one diamond on my ring fell out and obviously I lost it. I went back to the Sterns branch to get the diamond replaced. They refused to replace it because it was over a year old. And they claimed that I must have bumped my finger in order for the diamond to fall out. Honestly, how hard must you bump your hand / finger for a diamond to fall out. And there is no other damage to the ring. After a long forwards and backwards with Head Office, they agreed to replace the ring. Thank you for that.

When I went there to collect the ring afterwords I noticed that the diamond has been inserted a bit deeper than the others was. I didn't mind that, so I left that.

About another year after I collected my ring with the replaced diamond the same diamond fell out again and is lost. So there I walk around again with an engagement ring with a diamond missing! Very very embarrassing for myself and my fiancé.

I contacted the Sterns branch and once again, they refused to replace it because the ring is over a year old. So I contacted head office. A lady contacted me but wanted all slips from purchase etc. We don't keep slips for more than 2 year so I didn't have any slips.

She then advised that she might be able to pick it up on the system because my fiancé has an account with them. I have sent all information but haven't received any reply.

I am very upset because for most of the 4 years that I am engaged I have to walk around with a ring without a diamond. And I am very disappointed in the service.

This problem has now resulted in my fiancé that bought me another ring and the original ring is in my cupboard and I can't and don't want to wear it anymore.

I would really appreciate it if someone can assist with getting this sorted. To be honest, I don't want return it for another ring because my fiancé have just spend a few thousand rand on another ring. So I don't need a replacement. I actually just want him to get his money back.

Please can someone get this problem sorted for me as I have been trying to sort this out for more than 2 year no and no luck.