Most likely it's rusted fast to the shaft. They can be very difficult or impossible to get off the shaft without ruining them.

If you have time, use penetrating oil and heat for the next week and you might get lucky. If not, cut the outer portions of the pulley off and use a puller on the hub.

Did you remove the long bolt that holds the stacked pulley on the crank-shaft, after you removed the electric clutch? Might help!