Cannon Traditional 10756G / 10755G

i have had this cooker for just over 3 yrs brought from sainsburys. this has a design fault even though Cannon won't accept this. It's very dangerous and the knob handles get extremely hot, I reported this when I first got it and they said its the fan, so fixed that , yesterday it melted one handle and burnt 2, its not good enough, I got burnt turning it off, if I child touched it or an elderly person they would have been burnt seriously bad.

Luck for me I took out insurance, so this time I'm going to push for this to be sorted or the cooker to be replaced!!!