I have a ariston fm81R oven which is mis heating - ie: hotter at the bottom than the rest of the oven, additionally the bottom silver front plate has come away where it should affix to the oven at the top of the plate; and, third - when the oven is on the handle gets so hot is can burn your hand - is this normal? I have only recently moved into this house (existing oven) my previous oven was an ilve - please respond