You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I help you today?

USER: I am Christine Martin. Can you please reserve me a flight ticket which is having it's depart time in the morning?

ASSISTANT: Sure, Is the any class preference?

USER: I am ok with any class.

ASSISTANT: Please let me know your travel dates.

USER: I have planned to travel on Dec 23rd and return on Dec 25th.

ASSISTANT: May I know your airport codes?

USER: I would like to fly from PHL to LAX.

ASSISTANT: Do you have any other specifications?

USER: Yes, I would like to return at evening time.

ASSISTANT: Ok, please wait for a minute.

USER: Ok.

ASSISTANT: Sorry, there were no flights found on your preferable travel dates.

USER: Ok, no problem. Thank you.

ASSISTANT: Thank you for reaching us.