Canon Pixma MG6250 error C000 after paper was stuck and removed

After paper was stuck in the machine I took out the paperparts and now the display says "errorC000" and the waring light keeps flashing. Turning on and off several times with small and large intervals does not help. Canon has no other adivce than giving it to them for repair. There must be a simple way to put the faulty bit back into place.