Try this. Disconnect the electrical power. Turn it off at the panel breaker to the kitchen appliances or plug out the electrical plug from the wall outlet.
Once you do this, allow power to be off for about 15 - 20 minutes. Supply electrical power back to the appliance. May reset the internal circuity.
If that does not work and the door has a lever which you move to the closed/open position, it may be jammed, bent slightly or forced closed too much. Wiggle it genitally as you attempt to open/release the locking device.
May have to remove the front glass panel to access the locking device. Be sure electrical power is off before doing so.
If anyone else has this problem (w/Kenmore 911-47425) after you cancel the self-clean cycle, just press and hold the light switch; the "locking mechanism" resets itself and then the door will close. ( hopefully ) you won't have to open up the panel and disconnect the "locking arm" as I did... only to watch it "reset" when I closed the door... ugh.