1. Check to see if the main brush is installed correctly. If not, remove the main brush and reinstall it.
2. Check to see if the hopper is free from interference and that it is installed correctly. If not, clean the magnets on the hopper and on the machine and reinstall it.
3. Check to see if the main brush is clean. If it is not clean, remove the brush, clean it and reinstall it. If the main brush is clean, elevate the issue to the next level of support.
Additional Resource for Troubleshooting
How to Seat the Main Brush
How to Clean and Install the Hopper Magnets
How to Clean the Main Brush