CAT hoe E120B wont spin?

We have a hoe that wont spin, started off by working on and off. it would spin and work fine then all of a sudden it would not spin and it worked like this on and off for a couple hours until it would not spin at all. you can hear the motor and pump whine you could say as it it tries to pump fluid into the spin mechanism but when you try to spin it but it doesnt really move. if you hold the spin lever for a couple seconds it seem like the machine might move a tiny bit but it is hard to tell. replaced all filters recently if that helps any in asking for help. please respond with anything I will take any help I can get. Thanks

CAT hoe E120B wont spin?