I just cleared the plates and the waiter will now let me through to the next section to "chase" after the professor but he doesn't run away and continues to block the door. When I click on him he just says "No, I'm not hungry...I have more important things to do." I've looked at videos of this part and in those videos the professor disappears to the next section before Diggy can get to him. Any suggestions? At this point I can't move forward! Thanks.