You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, How may I assist you?

USER: I need to book a flight ticket from PHL to DTW as I should attend a board meeting.

ASSISTANT: Sure, May I know your name and travel dates?

USER: My name is Anna Robinson. My journey is on 08/20 and 08/22.

ASSISTANT: Sorry, No flights found with your preferable dates. Thank you for opting us.

USER: Ok, thank you for your response.