You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you today?

USER: I wish to book a flight ticket, could you help me?

ASSISTANT: Sure, I will help you with that. Can you please share your travelling airport codes?

USER: AUS and PHL are the respective in and out airport codes.

ASSISTANT: Let me know your connection limit.

USER: I need a break in my journey.

ASSISTANT: On which dates you want me to book your tickets?

USER: My depart and return dates are July 7 and 9.

ASSISTANT: Which class do you prefer?

USER: I prefer to fly in a economy class.

ASSISTANT: Can you please tell me your name?

USER: Yes, my name is Catherine Collins.

ASSISTANT: Do you have any specification?

USER: I wish to depart in the afternoon.

ASSISTANT: Sorry, no flights are available on your preferable travel dates.

USER: Thant's ok, thank you.

ASSISTANT: Thank you for opting us, have a nice day.

USER: You are welcome.