Hi Eddie,
Not sure what make of cooker you have but if it is a Stoves then the power to the ignitor is 240v and is supplied via a socket and plug in the cupboard underneath the cooker, this supply also provides power to the electric hob.
As mentioned before there is a gas cut off to the hobs so the lid needs to be in the upright position. There is also a manifold possibly in a nearby cupboard that has colour coded valves. There is a main valve and then a valve for each appliance, cooker, space heater and water heater. When the valves are in line with the pipe this is the on position.
It sometimes takes a moment for the gas to get through from the bottle, if the space heater is working on gas then your regulator and pigtails etc should all be fine, if no gas at water heater or space heater then looks like a regulator/ bottle/ pigtail problem.
David