While trying to light my forced air gas furnace, I get the 'primer' flame lit, let it burn for 1-2 minutes. When I release the button to allow the pilot flame to burn, the flame goes out and no pilot light. It has been reliable for many years. Any input will be appreciated. Thanks for any input. Chilled in Ky.

.(quote) When I release the button to allow the pilot flame to burn, { most gas valves that I`ve dealed with when you release the button you have to turn the knob/button to the on position which opens the gas to allow gas to come out feeding the pilot and for the burners when needed,, I say this not knowing what kind of furnace or gas valve you are dealing with

Often the issue can be the thermocouple if it will not stay light after releasing the button.

Gas Furnace Pilot and Thermocouple - How to Light a Furnace Standing Pilot