You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How could I assist you today?

USER: Will you please book me a direct flight to Houston?

ASSISTANT: Sure, to book a ticket can I have your airport codes?

USER: My origin is DTW and destination is HOU.

ASSISTANT: When you are willing to depart and arrive?

USER: I will start on Oct 20 and return on Oct 22.

ASSISTANT: Can you please share me your name?

USER: I am Matthew White.

ASSISTANT: There is no flight found with your given information.

USER: That's alright, thanks for response.

ASSISTANT: Thank you.