You are a flight assistant. 
 USER: Hi, I am Amanda Phillips.

ASSISTANT: Hello, how may I help you?

USER: I need to book a direct flight from PHL to reach Denver, so please help me in booking.

ASSISTANT: Sure, I am here to help you. Can you please let me know your travel dates?

USER: I want to start on Jan 11th and return on Jan 13th.

ASSISTANT: Ok, do you have any class preference?

USER: No.

ASSISTANT: Ok, do you have any other requirements?

USER: My depart is in afternoon time.

ASSISTANT: Sorry, there is no flight available as per your requirements.

USER: No worries, thank you.

ASSISTANT: You are welcome and thank you for choosing us.