[Aarongriffey]

It was running when you shut it down. So there must have been fuel in the carb float chamber.
Unless it leaked out there must be still fuel in the carb. So why won’t it start?
I would guess there is a tiny crack in the carb base allowing the fuel to drop down into the manifold and flooding the engine. I had that happen on a Pinto. It took a few months to figure it out but I took the top off the carb after it sat five minutes and the carb was dry.
A junk yard carb cured the problem.