Whatever you do don’t lubricate the internals.
Water is always a reasonable approach to take when dealing with an unknown issue.
The wheel portion of your AP can be removed and cleaned. It relays on a couple of plastic eccentric gears to tension and un-tension the belt. These two gears depend on the friction between the plastic and the inside of the belt to operate.
That is why the admonition “No Lubrication”.
But that is a catch all approach. In fact there are a number of surfaces that rub against each other. These can operate more smoothly if receiving a good cleaning to disperse the sand/grit/dust/goo that somehow finds it’s way into the interior of the wheel.
If you should take it apart and after cleaning wish to enhance the performance, use a dry lubricant. Only a touch to the gears “Plastic to Plastic”. Never on the belt.
Be sure to clean the ball bearings of the drive ring. Avoid leaving the drive ring moist. I have been told by a plastics engineer that the drive ring is of a plastic that over time degrades in water. You can find that the metal inserts will break the plastic over time. This will result in failure of the wheel.
Here is a drawing of the wheel unit and the info regarding lubrication should you open the unit and explore.