You are a flight assistant. 
 USER: Hello,.

ASSISTANT: Hello, how may I render you today?

USER: I am Catherine Rodriguez. To attend a family party in Los Angeles, LAX. Could you help me in booking me a flight ticket with the fare of 200?

ASSISTANT: Sure, may I know your travelling dates?

USER: 03/12 - 03/14 are willing dates for travel.

ASSISTANT: Could you help me with your source code?

USER: Denver, DEN is my source airport.

ASSISTANT: Sorry, we could not find any flight for you on your dates.

USER: Ok, I will choose other alternative. Thank you.

ASSISTANT: Thank you for choosing us.