I'm cruising into Shanghai Mar 17 arrive a.m leaving p.m confused whether I need a visa or not

In principle, after stopping in Shanghai, if the cruise will head to a third country or region different from the last one it came from, you may be able to enjoy the 24 hour direct transit. But as you said, the cruise company said that a visa is needed. In this case, you need to provide a visa, otherwise, you may be refused to board the ship.