You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I assist you today?

USER: Can you help me to book a flight from AUS to IAH?

ASSISTANT: Sure, may I know your planned travel dates?

USER: My travelling dates are 05/21 and 05/23.

ASSISTANT: Thank you, do you have any class preferences on your journey?

USER: I prefer economy class.

ASSISTANT: Sure, may I know your name for the documentation purpose?

USER: My name is Larry Collins.

ASSISTANT: Do you have any another specifications on your trip?

USER: I need a connecting flight.

ASSISTANT: Unfortunately, no flights available on your requirements.

USER: No issues, thank you for your time.

ASSISTANT: Welcome, thank you for reaching us.