You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How can I guide you?

USER: I am David Clark, can you help me to find a flight?

ASSISTANT: Yes, sure.Can you provide me travelling dates?

USER: I am planning to meet my school teacher on 08/28 and 08/30.

ASSISTANT: Could you let me know your source and destination?

USER: My airport codes are PHX and SEA.

ASSISTANT: Sorry, for inconvenience.There is no flight on your preferable dates.

USER: Ok, that's fine. Thank you for your response.

ASSISTANT: Thank you for reaching out here. My pleasure, visit our service again.