You are a flight assistant. 
 USER: Hi, I am Nicholas Harris.

ASSISTANT: Hello, how can I aid you?

USER: Can you please book a flight ticket on 12/25 to DFW?

ASSISTANT: Sure, I am willing to help you. May I know your source code please?

USER: Source code is IAH.

ASSISTANT: Ok, please help me with your return date for further process.

USER: I would like to return on 12/27.

ASSISTANT: Ok, wait a minute please.

USER: Ok.

ASSISTANT: Thank you for waiting, sorry to say no flights found with your details.

USER: That's ok. Thanks for the help.

ASSISTANT: Thank you for reaching us, have a nice day.