Diamond not secure in setting and no resolution from store

Please could you assist me with my complaint. My husband purchased my engagement ring 5 years ago , within the first year my ring was returned as the diamond was loose. the ring has been back several times since for the same problem . more than a month ago I returned by ring to the Pavillion store who has had it now for almost 5 weeks and it has been returned twice in the past month. Each time I received no contact from the store but had to make several calls myself . I was assured the ring was fixed and the diamond secure. When I went in to collect , upon checking the diamond was still moving in the setting. The ring was sent back to the workshop and i was told i would be contacted within a couple of days .... after no phone call I phoned the store and was told the ring was back and fixed. I went in again to collect and again the setting was not secure and the diamond was moving . I was told that the manager would contact me and the ring would be returned to the workshop. No call was received. I called in again and was told by the manager she would contact me on Tuesday afernoon.. it is now Wednesday evening and yet again no phone call. This type of service is absolutely terrible , each time i have called in I have been asked for my phone number . after so many returns of my ring I would have thought that the manager should know who I am and after all my records are in the store ?? yet no-one phones do you have soo many rings with loose settings that you are not able to keep track ?? I have noticed that you have lots of complaints on the internet of bad service , lost stones and broke settings I was told that my setting is such at I have been "hard" on the ring ?? I have rings purchased from other retailers , some that are 30 plus years and some inherited that are 50 plus years old and never had a problem with a moving diamond. Rings are made to be worn not to be kept locked away ?? please advise urgently as to a resolution for this ??