ASME propane tank leak

My permanently mounted ASME tank is under the van on my 1997 Class B Xplorer. I used it 10 days ago just fine. I drove to PA and as I started to turn on the valve I could hear wooshing gas and felt the cold on my hand and the smell. I turned it off right away. I tried again a few times with the same result. The next day it did not make the wooshing sound & I did not feel the cold, but I did smell some gas. So it has stayed off. This happened once before in 2019 when I wanted to check my furnace before driving to FLA in January from Michigan. When I made Tenn it was good and has been good since. I note both times it happened I had been in freezing temps.

I am getting by as I am always plugged in to shore power on my current trip. When I get home I will try to find some company to either replace that valve or the whole tank as it is old and even though I repaint it often it's age is showing.