There are two primary reasons that is happening. Either the red knob has stripped and is spinning freely around the nut inside it. Or the threaded rod that feeds up to the control arm has stripped. If that is the problem please contact us at the number below. You will need the receipt. Most likely, however, it is the knob.
The FrontLoader has used two different knobs. You can determine which one you need by looking at the threaded rod the knob is attached to.
If the rod has a tapered end use part number 8880226
If the rod has a blunt or squared off end use part number 8880766