dpwct

I have been having problems going up my 2019 430ix

The pump shuts off prematurely, thinking the tank is full when it is still very low.

happens at every gas station does not matter which way I put the pump in

seems like it might be either the vent valve or the charcoal canister filter would like any thoughts on that as the charcoal canister $500 is much more expensive than the vent valve $100

any thoughts on what I should have my mechanic check or replace. I’d like to avoid spending a lot
Until I’m sure what it is