Propane Control Valve Failure

[hummingway]

My propane has become flakey. In the morning the stove won't light. Usually later in the day, I presume because it's warmer it will but it went out a couple of times and seems fluctuate. The first time it didn't light I new it was ready for a refill so removed the tank but at the time thought it was odd that there was a tiny amount still in the tank. My control valve is a advanced fuel components (AFC) model 121 and the switch panel a marinetics. Before try and find a new valve to purchase, has anyone an experience with this? Is it possible a valve replacement is not required?
Thanks.

[hummingway]

I closed the tanks valve and turned on the control and then turned on a burner. Once the pressure gauge indicated 0 I turned off the stove opened the valve and the burner lit fine. If it works in the morning I'll post in case it is a fix for a problem someone else runs into.