You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am Joshua Clark from Houston.

ASSISTANT: How can I help you Clark?

USER: Can you please book a flight ticket from IAH to PHL?

ASSISTANT: Ok, please provide me the ravelling dates.

USER: Sure, I need to travel on dates of 11/16 and 11/18.

ASSISTANT: Please wait a moment. Let me check with the details.

USER: Sure, take your time.

ASSISTANT: Sorry, there are flights with your credentials.

USER: Oh! It is sad to hear. Anyway, thank you for your time.

ASSISTANT: You are welcome.