You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How may I help you?

USER: This is Jacob Johnson, would like to travel from HOU to LAX. Can you help me to book a flight?

ASSISTANT: Can I know your travelling dates?

USER: Sure, my dates will be 03/18 and 03/20.

ASSISTANT: Just hold on for a second.

USER: OK.

ASSISTANT: Sorry for inconvenience, there is no flight available.

USER: Oh! that's fine.

ASSISTANT: Thank you.Have a great day.

USER: Thank you for your supportive service.