Hotpoint gas dryer

I didn't go down and find model number but I think most have the same theory of operation. It is 7-8 yrs old. Vent is not plugged ,lint filter is clean and there is a good air flow out the vent. It has been in the same position for years.

I never know if clothes will be dry or wet when I go down to get. When it DOES light I hear the click and then the flame come on. When it doesn't light I do NOT hear the click and it does not light.

If I am standing, waiting and I don't hear the click I move temp selector from heat to no heat and back to heat. It may or may not click as it would when trying to light and when it does click it doesn't always ignite.

Thanks