I'll contact currys and get someone to repair it for me as I am not able to check these things myself. Thank you for your recommendations.
Currys couldn't help because the hob is about 17 years old. I decided to contact the manufacturer who quoted me a price for repair which would be similar to purchasing a new hob, therefore I have decided to buy a new hob. I should have phoned the manufacturer in the first before spending the £22. However I appreciate that you could do no more than you have done to assist me.