This indicates motor fault.
You may unplug it and pull it out then remove the top off the appliance.
Check if the belt is intact, if the belt is fine then remove the rear panel and then check if carbon brushes inside the motor are worn out.
If they are then replace it and issue should be resolved.
The part is available for £29 + repair charges, to order the part please "click here".
If you want to replace it yourself, this "video" will give you an idea on how the replacement is done.
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