There should be a facepalm emoticon, cause I thought of this strip this exact situation came up this afternoon.
ME:"Data is supposed to show up"
Manager: "No, no data is a good thing, it means you've done your job!"
ME: "I can prove I didn't do my job"
Manager: "We fixed it a month ago"
ME: "Well your supervisors didn't really clarify what was supposed to happen, is there any code or documentation about the code being changed?"
Manager: "uhhh...let me talk to my supervisor"