I've only just got my halogen oven and have found that when the timer dings and it turns itself off, if I take the lid off to take food out, it won't start again when I put the lid back on. I've tried unplugging it and plugging it back in, turning the timer and temperature to 0 and back up again, and I'm pushing the handle down. The only thing that has worked has been taking out the black cable that goes into the lid and then sticking it back in. Then it turns back on ok. Is this normal or should I take it back???