You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I help you?

USER: I want to travel from CLT to PHL. Can you help me to book a flight ticket?

ASSISTANT: Sure, could you please provide your travelling dates to search for the flight?

USER: I want to travel in the flight on Apr 11 and Apr 13.

ASSISTANT: Do you have any requirements?

USER: I prefer to travel in economy class.

ASSISTANT: May I know your name?

USER: I am Betty Johnson.

ASSISTANT: Sorry to say, no flight is available for you.

USER: That's ok. Anyways, thank you for your help.

ASSISTANT: Thank you for reaching us.