Reese Cooks - S2-E18
Continuity mistake: During one of Reese's cooking classes, Hal puts some bread into a toaster. It then cuts to a shot of Reese. When it cuts back to Hal, the toast that pops out of the toaster isn't the same shape as the bread he put in.
Answer: Francis is only allowed to talk on the phone at school for three minutes a day. I think the code gives him free access to talk to his girlfriend.