Have you checked the upper spray arm to make sure all the holes are clear on both sides. Some holes are there to push the arm sideways. If they are blocked it will not rotate. F&P service agents like all franchise so called specialist trained technicians are expensive, overpriced and usually no better and quite often worse than non specific brand techs. Suggest you give F&P a miss and try someone else.
Lincoln Appliance NZ, May 2010