I agree with IAMICHABOD
Before spending a lot of $$$...
I had the same issue with a 2004 Roadtrek camper van. If I turned the gas pump handle at 45 degrees or so angle, it would pump the gas with no problem. Try experimenting different angles to get the best result. I found some gas stations didn't need the angle adjustment. It depends how fast the fuel was pumping. Sometimes a sharp bend in the filler hose prevents proper air ventilation and turning the pump handle can alleviate the issue.
My new rig does not have this issue I'm happy to say. Best of luck.