answer: #Person2# didn't call #Person1# because #Person2#'s phone was taken away by #Person2#'s teacher.
documents: #Person1#: Why didn't you call me yesterday? I was waiting by the phone all day.
  #Person2#: I'm sorry, I couldn't call. I couldn't find a phone.
  #Person1#: What do you mean you couldn't call? You have a cell phone, don't you?
  #Person2#: I used to have a cell phone. The teacher took it away because I tried to call you from class.