The clutch (brush control) has become stuck. The clutch belt cover needs to come off to find out what the blockage is. The soleplate, brushbar, lower hose and brush housing all need to be removed to get to the 3 belt cover screws. Often, a small object can be flicked by the brushbar into the clutch mechanism. You may get a result by manually turning the brushbar with the soleplate removed, this may clear the obstruction without having to remove all the other parts.
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