Disharmony - S2-E17
Continuity mistake: When Cordelia and Harmony are on the couch talking and drinking, the towel on Cordelia's head goes from on her shoulder to behind in the change from wide to close up. (00:10:30)
Disharmony - S2-E17
Continuity mistake: When Harmony enters Cordelias bedroom, the strap on Corelia's shirt falls off her shoulder and then magically is back in place after the angle change. (00:13:50)
Disharmony - S2-E17
Continuity mistake: In 'Disharmony' Willow's hair is over her eye when she says "Thanks for the affirmation", but when we see her again a second later its tucked behind her ear. The shot wasn't on Cordelia long enough for her to have tucked it back. (00:16:45)
Disharmony - S2-E17
Other mistake: When Harmony spills her pig's blood on the keyboard, the computer shorts out, and the monitor flickers off, but the mouse cursor is still visible. (00:25:35)
Disharmony - S2-E17
Other mistake: At the very end, as Angel walks out the door he reflects in the panes of glass on the door. (00:42:10)
Disharmony - S2-E17
Continuity mistake: In some of the shots in the scene with the red bird, it is raining and in some shots it is not.
Disharmony - S2-E17
Continuity mistake: When Angel pulls Cordelia aside and says that Harmony cannot work with them, a man in the background walks past in the shot of Cordelia but we never see him walk past in the shot of Angel.
Answer: Everybody including Angel saw her. After helping them and then being left alone to talk to Angel, Cordelia says that the Powers That Be let her come back one more time to help them. After Angel gets a call saying that she died, he realises that it was her spirit that was helping them the entire time.