answer: #Person1# didn't attend #Person2#'s birthday party because #Person1# has a new email address and didn't receive the invitation email. So #Person1# invites #Person2# to lunch to celebrate #Person2#'s birthday.
documents: #Person1#: Wait, Ben, did you say you had a party Saturday?
  #Person2#: Yeah, you didn't know about it? It was my birthday.
  #Person1#: No, I didn't.
  #Person2#: But I've invited you. I sent you an email last week.
  #Person1#: Are you sure? I didn't get it. Oh, you know what? I didn't tell you I have a new email address. Oh, I am sorry.
  #Person2#: That's ok, but I was kind of upset but you weren't there.
  #Person1#: Listen, let's go out for lunch this week. I want to do something for your birthday.
  #Person2#: Oh, you don't have to.
  #Person1#: I know, but I want to.
  #Person2#: Ok, that's really nice of you, really. So anyway, I have to go now. I have a meeting at 9:30.
  #Person1#: Ok, see you later and Happy Birthday.