You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am Ryan Lewis.

ASSISTANT: How can I aid you?

USER: I would like to go to long trip to enjoy myself, can you please help me to book a ticket?

ASSISTANT: Can I know your planned dates of trip?

USER: I have planned my dates on 04/24 and 04/26.

ASSISTANT: Ok, please mention your airport codes.

USER: My airport codes are from HOU to OAK.

ASSISTANT: Please wait for a moment.

USER: Ok, I will wait for your response.

ASSISTANT: Sorry Ryan, no flight is available on your route.

USER: Ok, no problem. Thank you.

ASSISTANT: Thank you for contacting us.