Gas leak/issue

I head out to the grocery store to grab everything needed for dinner.
Then the gas runs out.
I call everyone I know, but apparently, nobody is available to give me a lift to pick up a tank.
So, I decide to walk. I trudge back home, drenched in sweat and smelling like a brewery.
I finally get the tank set up and...
😕I can't even budge the main valve on the cylinder...
🙏 Send help before I lose my mind.

1. Crank up the friction between the valve and the seat.
2. Put more force on the valve itself.
3. Lengthen the lever arm to get more leverage.
4. Throw all of that together at once.