Late 90's model Mercury 3.3hp issue

Got it all repaired and running for about $320, ran great for about 2 months now it wont start. Took the cowling off, and theres no gas in the fuel line that goes into the carb. Theres a little valve below the gas tank to turn the gas on or off, and its wide open. Fuel in the gas tank.
Help would be appreciated.

Internal tank? I would take fuel line from tank off look and blow through it. I may not be ethanol resistant.

All 3.3 have the ethanol problem. Take the valve off and clean the screen.