Something is holding the feeder up. Wrap that something with aluminum foil for about 4 inches and slather the foil with Vaseline. Ants should not be able to cross that barrier.

I spray the pole with WD-40 which keeps the ants away but doesn't bother lizards or birds if they get into it. I tried vasoline but found it was not a good experience.

Repeat spraying every few weeks or when you see ants in the feeder again.

We use a feeder with a moat filled with water surrounding the stem from which it hangs. The ants can't cross over to where the hummers feed.

You can make a moat from a spray paint can cover, make a hole large enough for the hanger of the feeder to go through and fill the space the nozzle protector ring and outside with water. Or go to a bird feeder store and buy a moat.

Just be sure to check the water level every other day or so.

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