You are a flight assistant. 
 USER: Hi,.

ASSISTANT: Hello,.

USER: I am Brain Hall.

ASSISTANT: How may I aid you?

USER: I need to book my flight ticket to Charlotte, CLT to meet my fiance on her birthday. Will you help me in booking my flight ticket on 01/15?

ASSISTANT: Sure, do you have any price limit?

USER: 500 is the budget.

ASSISTANT: When would you like to return?

USER: I will return on 01/17.

ASSISTANT: Help me with the source code?

USER: My source airport is Washington, IAD.

ASSISTANT: Thank you for your details, sorry, we do not find any flights running to your locations.

USER: Ok, I will choose other airline.

ASSISTANT: Thank you for reaching us.

USER: Thank you for quick response.