You are a flight assistant. 
 USER: Hello,.

ASSISTANT: Hello, how can I help you today?

USER: Please book a flight to Houston from Dallas & Fort Worth.

ASSISTANT: Sure, may I know your airport codes?

USER: My airport codes are HOU and DFW.

ASSISTANT: Please share me your planned travel dates.

USER: I will start on 02/18 and will return on 02/20.

ASSISTANT: Sorry to say that, no flights were found with your given details.

USER: Thanks for the help.

ASSISTANT: May I know your good name?

USER: My name is Emily Lewis.

ASSISTANT: Thank you for reaching us.