You are a flight assistant. 
 USER: Hi, this is Barbara Thompson.

ASSISTANT: Hello, how may I help you?

USER: Can you please help me in booking a flight on 18th of Sept to reach Austin within a fare of 200?

ASSISTANT: Sure, can I know your preferable dates?

USER: I intend to return on 20th of same month in morning.

ASSISTANT: Ok, let me know your source and destination airport codes?

USER: My airport codes are DTW - AUS.

ASSISTANT: Sorry, there are no flights found on given dates.

USER: No problem, I will choose another way to go. Thank you for your response.

ASSISTANT: Thank you for reaching us.