customer: Hello. 
 agent: Hello, how may I assist you? 
 customer: I need your help to book a flight ticket on 11/18 and 11/20. 
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 customer: Sure, my origin code is NC-CLT and destination code is CA-SFO. 
 agent: Sorry, unfortunately there is no flight in these travel dates. 
 customer: OK, that's fine. 
 agent: May I know your name please? 
 customer: Sure, I am John Thomas. Thank you. 
 agent: Thank you, have a good day.
agent: OK, may I know your origin and destination airport codes?