answer: #Person2# is answering #Person1#'s inquiry about an unreceived bill which computer shows already been mailed. #Person1# asks for an extension, while #Person2# requires proof of fault.
documents: #Person1#: I was inquiring about a bill that I never got.
  #Person2#: Which credit card was the bill for?
  #Person1#: The bill was for my Master Card.
  #Person2#: That bill should have been mailed about two weeks ago.
  #Person1#: It never came in the mail.
  #Person2#: My computer shows that it has already been mailed.
  #Person1#: I have not gotten my bill, so what should I do about that?
  #Person2#: You should try contacting your post office.
  #Person1#: If it is the post office's fault, may I have an extension on my bill?
  #Person2#: You'll have to prove it was their error ; then you can get an extension.
  #Person1#: Thank you for all your help.
  #Person2#: You are very welcome. Have a good day.