Arthur - You do not mention where you live.

In Massachusetts and many other states, the pumping system contains a vapor recovery system.

The system is sealed by a bellows (that people hate!) or in other cases has a small tube in the nozzle to suck vapors out of your tank as the fuel goes in. Often the hose is a double hose with a vapor space surrounding the fill hose. This is to reduce vapors in the atmosphere - a gallon or more of vapor for every gallon pumped.

If people top up like I see many do, gasoline can get into this outer vapor hose and bugger up the system.

This fuel can come out as soon as you squeeze the handle, sometimes even before.

This happened to me when I tried to put fuel into a brand new loaner - an XC60 with 35 miles on it! It covered the entire rear behind the wheel.

I washed it off with the windshield washer stuff and went in to tell the attendant - he came out with a bucket of soapy water and a sponge! This taught me a lesson.

Now I always dip the nozzle down before I bring it to my car. Occasionally I do get a drib of fuel.

Have you tried another station?

When you say overflowed, do you mean that the nozzle clicked off, and not that gasoline poured out of the opening? Did you try a different pump?

I found that not all nozzles are created equal, and some need to be pulled back a little (1/2 inch) to work correctly. I have never gotten used the the California style accordian nozzles that need to be pushed all of the way in before the pump will work.

If you suspect that the vent hose on the car is blocked, that is an entirely different issue. Note: spiders and wasps cannot block the vent tube, the vapors will kill any insects, besides the fact there is no outside access to the vent tube.
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My back feels better when I sit in a Volvo seat