I've got a Kenwood electric mixer I've used for...

The question poses yet another question which needs to be known. Does the machine have a reverse switch - If so, that switch may be stuck in the opposite rotating position, regardless of what position the indicator is in.
If there is a reversing switch, testing it using an ohm meter may reveal it is not allowing the motor to run in both directions. If there is no reversing switch, next to be known would be if the motor is reverseable...
If motor is not reverseable or never was reverseable, being sure it is infact currently reversing. May be more than meets the eye and more info specific to that models operations and functions that need to be known to allow more specific help to be provided.
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