Gas fill problems

I have a 2002 Hyundai XG350L with 90M miles and recently started having this problem. Whenever I try to fill up the car the nozzle shuts me off after a few seconds. I have to just barely let the gas flow and it takes forever. I have had the Charcoal canister and a close(?) valve replaced by a dealer but still having the problem. I have been told by a local mechanic that there is another valve that may be the problem but that requires removing the gas tank. Any suggestions?

Is the filler neck vent clear? Shove a heavy duty weedeater string down the pipe (It’s a small diameter pipe).

I hate to hear that the dealer used an unregulated GUESS-O-METER on your car, and changed the wrong part for a gas tank fill problem.

Your local mechanic is far wiser. There are two, or three, valves (vent, anti-spill, something) inside the gas tank which can cause fill problems.
You might be able to get a good gas tank from the salvage yard; or, have your gas tank troubleshot and repaired.

Have you been in the habit of of topping off the tank?