whirlpool gas hob creating clicking but no spark

Hi guys i reported that only 2 of rings were sparking, but now none are, when you press the button , all you can hear now is a very faint clicking noise, and not producing any spark what so ever,

I have had all of the contacts apart and cleaned all 4 of them, but have not made a difference whats so ever,
i dont know if i can check them one at a time as normal working mode they all spark at the same time, so i presume that if one is faulty it will not create a healthy spark ?

help please