MF, first thing I would do is remove the chain and bar
Look underneath and there should be an oil feed adjustment screw (sometimes not). Max the screw out, then start and warm it up for a few minutes then run it about 1/4 throttle.
Quite likely what ever is blocking it will clear out
Next step is empty the tank and fish out the filter and see if the oil has congealed in it
Unfortunately leaving oil in them is the worst thing for the saw since the added tackifiers in bar oil tend to set like sludge in some brands
