Hrm. Sounds like the low speed jet may be clogged - The orifce is TINY, easy to block. May want to check that the float is moving too.
Take it off, take it apart, HOSE IT DOWN in every hole with carb cleaner. BLOW out all the holes with a compressor. Set all the mix screws to stock and put it back on.
If it is a 2 stroke, check out the reeds to see if they are bent/chipped/mangled/dirty.
If it doesn't fire after spraying starting fluid in the plug hole - Something else may be a problem. Make sure the park plug is fresh and properly gapped.