I had this problem some years ago, it stuck in causing a serious incident. Get it looked at as recommended by the Prof.For safety you should arrange to have the hob checked by an approved gas engineer.
All good. Embarrassing moment as I was trying to light the heat plate on the hob. That’ll teach me not to have too many beers before trying to cook.
Most of us have been there and done that. Mrs H said the Califlower cheese is taking ages to cook, she had it in the main oven, but had the grill on. Oh well another bottle of wine.