Poor craftmanship

So I bought myself a ring at sterns,bloemfontein loch logan on the 7th of August.On the 23 Sept the centre stone is missing and when I imspect the ring I find that some piece which hold the stone is totally broken.So I took it back and it was repaired yes and fast.But my concern is poor craftmanship on the ring.It took only 1month and about two weeks and then it just broke,I did not expose it to anything that could have resulted in it being damaged.So please sterns do proper quality check please.I do not expect such things when I buy something from your store.