How deep is the pile on your carpet? If it is normal pile take the bottom plate off and remove the two rope seals in the narrow channels of the plate. Always start your vacuum cleaner in the upright position if it is clutchless and let it get up to speed before lowering the cleanerhead this will save your belt.
My other method to help you push your cleaner over a deep pile carpet is a last resort only so I will wait to see if you still have a problem.
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