Henry: What's the entrance code?
Jessica: To the lab?
Bobby: 7898
Henry: This is what I thought but it doesn't work
Bobby: That's strange
Bobby: It worked yesterday
Jessica: They sent us an email yesterday that they would be reseting the system
Henry: Oh no! Today?? 
Jessica: I'm afraid it's today
Jessica: But maybe you can talk to the administrators to let you in if it's urgent
Bobby gives Henry the entrance code but it's invalid. This is due to today's reseting the system but Henry can still contact the administration.