You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am Joseph Clark.

ASSISTANT: How may I assist you?

USER: Can you help me booking a flight ticket from PHL to SEA?

ASSISTANT: Sure, may I know your travel dates?

USER: I will start on 04/20 and return on 04/22.

ASSISTANT: At what time do you like to travel?

USER: I need to return in the morning time.

ASSISTANT: Sorry, there is no flight on your details.

USER: No problem, thank you for the information.

ASSISTANT: Thank you.