Why do the side brushes rotate slowly or not rotate at all while DEEBOT is cleaning?

(1) When the battery level is low, DEEBOT will automatically switch to Returning to the Charging Dock mode. In Returning to the Charging Dock mode, the rotation of the side brushes slows down. The robot can start cleaning again once it's fully charged.
(2) Something is entangled in the side brushes and makes it unable to operate, check and clean the debris.
(3) The side brushes were not correctly installed. Remove and reinstall the side brushes.
If the problem persists, please contact ECOVACS Customer Service.