Product didn't work - refused refund or credit

We purchased a Cyclone Sewer Vent from Camping World. It is made by Camco. It is advertised as fitting "any plumbing" on any RV. However, it did not fit our RV piping, and there were no adapters provided to make it fit. I contacted Camco and requested credit for something else of theirs that would work with my RV, but they refused. I asked for contact from the owner, but I was never contacted.