04 Impala won't take gas.

Hey all! Im new to this forum. I'm looking for help with my 04 Impala 3.4L. Went to the gas station to put gas in my car and come to discover the gas won't go down the filler neck. I think the tank is literally airlocked. There is a new vent solenoid on the car and the purge valve up front seems to be working. Is there a way to test if the tank is airlocked. It's not the "pump is shutting off at the station" the gas just won't go down the filler neck and spills all over the ground. Would it possibly be the canister on top of the tank? Pretty sure the filler neck is not blocked! Any info or advice would be appreciated. Thanks in advance