Has anyone has any problems using Charleston Alexander Jewelers in Bethesda, MD? I ask because my fiance bought (on October 1, 200 a platinum 1.0 carat shared prong e-ring into which he had them put a center stone. When setting the center stone, for some unknown reason, they used 14k white gold solder. The ring immediately started turning yellow where the prongs meet the band and Charleston Alexander will do nothing to correct the problem. They altered a perfectly beautiful, new Memoire ring and will not provide any corrections to the problem that they created? Any advice on how to proceed?