Diamond fell out within four months

i'm really disappointed in the service that i got from American Swiss. I wore my wedding ring for only four months and one of the diamonds fell off. I took my ring for repairs on the 2nd of June 2015 till today my ring is still with them, and when i brought in the ring for service i was told it's only gone take 3 weeks. when i get to the store i was told that the ring is in cape town with the quality assurance people and i feel like nothing is being done hence they keep promising that they will call cape town to get feedback why they are taking long. I feel that you cannot promise a customer to call and not provide feedback to the customer. Bad service seriously and i feel that i'm no longer going to buy my jewelry if this the service i'm getting from them. If they cannot repair the ring why not give me a new ring. it cannot take 7 weeks to repair a ring.