Potterton Kingfisher II piolt light won't stay lit !?

Hi
I followed your steps on igniting the pilot on my Potterton KingfisherII. The pilot lights when pressing the ignition button keeping the left hand button with the start at the marker depressed for 30 sec+ but on releasing it to turn the left hand button to match the flame with marker the pilot light goes out. I have restarted the process several time keeping the button depressed longer each time but the light goes out as soon as i realease it. What else can i do to light the pilot? We're a family of four without heat and hot water and it's 9.30pm...can anyone help?