Issues with new Fisher-Price Rainforest Jumperoo?

My parents bought my 6-month-old son the Fisher-Price Rainforest Jumperoo. My husband is putting it together right now, and once he put the seat into the circular base it's ridiculously hard to turn the seat in the 360 degrees it's advertised to be able to turn for them to play with the toys surrounding them. We had a hard time turning it with our arms, so our son will have no chance of turning in it himself while suspended from springs. Has anyone else had this problem? Are we doing something wrong? Is it defective and need to be returned?