answer: #Person2# wants to exchange a sweater for a larger one with a receipt.
documents: #Person1#: Yes, ma'am. Can I help you?
  #Person2#: Yes, I'd like to exchange this sweater.
  #Person1#: What seems to be the matter?
  #Person2#: Well, you see, I got this as a birthday present, but it's the wrong size.
  #Person1#: Do you have the receipt?
  #Person2#: Yes.
  #Person1#: Could I see it, please?
  #Person2#: Well, here you are.
  #Person1#: What size do you want?
  #Person2#: Just one size larger.