Horrible jewellery designing

When you get Diamonds & pearls to make you a engagement/wedding ring, after which alterations need to be done twice (since they did a horrible job the first time)... only to have your diamond fall out of the ring with no effort only after at most 2 months later after getting your ring back, when surely a diamond shouldn't just be able to fall out with no force or pressure to the ring what so ever.. absolutely terrible workmanship