[speaker001:] Could I have my bill, please?
[speaker002:] Certainly, sir.
[speaker001:] I'm afraid there's been a mistake.
[speaker002:] I'm sorry, sir. What seems to be the trouble?
[speaker001:] I believe you have charged me twice for the same thing. Look, the figure of 6.5 dollar appears here, then again here.
[speaker002:] I'll just go and check it for you, sir.