First, I would make sure it is clean. In my Bosch the dough has a tendency to climb the spindle and get into that joint. If that is not the problem, then check for burrs or rough spots on both the spindle and inside the paddle/hook. Finally, lightly swab a little food grade mineral oil (available at your local pharmacy) on the spindle and inside the hook/paddle. I use a cotton swab (Q-Tip or similar) for this. One or all of these should at least help.
First, I would make sure it is clean. In my Bosch the dough has a tendency to climb the spindle and get into that joint. If that is not the problem, then check for burrs or rough spots on both the spindle and inside the paddle/hook. Finally, lightly swab a little food grade mineral oil (available at your local pharmacy) on the spindle and inside the hook/paddle. I use a cotton swab (Q-Tip or similar) for this. One or all of these should at least help.
Good luck!
OldWoodenSpoon