Appalling service

I have both. Car and household insurances with Iwyze, I took over after my husband died the one of household. I claimed for my double oven that was not working. They brought the assessor who told me it is the foil I covered the base of small that causes it not to work and because big one find out is working and still has foil in it. I told this Sean assessor that when purchased this oven in 2017 I covered both ovens with foil and I never had problem and I dominantly cook my food covered with foil, his reasoning makes no sense. He got angry and promised me that he will write a good report to the insurance company. Later I received rejection email and I responded with the same breath but I never got response till today.