I want to drain some coolant so I can replace the thermostat. Jacked and stands under the front jack points. Removed the covers underneath and opened up up the collant tank cap. Drain plug is not like the manual, its on the side, recessed, and has a yellow stripe across it. I turned it 90 degrees ccw, and nothing. stuck a pin punch up the drain hole, I can feel it hit the plug but again, nothing. The drain hole has no old dirt or gunk in it.

Am I missing something here? when I turn the plug 90 degrees ccw, it feels like it hits a stop. I don't want to force it. What to try next?

Thanks in advance