DIAGNOSIS A jammed or seized brush roll. Something (like a rug tassel, hair, or string) has wound so tightly it's locked the mechanism or burned out the drive belt.
FIX Unplug immediately. Flip the machine, release the two latches, and remove the brush roll cover. Manually try to turn the brush roll. If it won't budge, use scissors to meticulously cut and remove all wound debris from both ends of the roll. Once free, manually spin it to ensure it rotates smoothly. Reassemble and test.
IF THAT DIDN'T WORK If the brush roll spins freely by hand but not when powered, the drive belt has likely snapped or slipped off its motor pulley. This requires accessing the belt housing, which may need a tool.
HEADS UP The humming noise is the motor straining—if you let it continue for more than a few seconds, you can overheat and permanently damage the motor. Always unplug first when investigating a jam.