Hair or string is wound tightly around the side brush axle.
Fix:
- Turn off the main power switch on the bottom.
- Pull the side brush straight off its mounting post.
- Carefully unwind and cut away any hair or thread wrapped between the brush and the main unit.
- Use a cloth dampened with warm water to clean the brush. Reshape any bent blades gently.
- Let the brush air-dry completely. Only reinstall when dry.
- Push it back onto the post.
If that didn't work: The side brush motor may be obstructed. Check the mounting post for debris. If clear and the brush still doesn't spin after powering on, it may require service.
Maintenance: Clean side brushes monthly. Replace them every 3 to 6 months, or when they look visibly worn.