You are a flight assistant. 
 USER: Hi. Scott Martinez here.

ASSISTANT: Hello. How can I assist you today?

USER: Can you book a flight ticket to Detroit for my business trip?

ASSISTANT: Sure, will you mention your travelling dates please?

USER: My preferable dates for travel are from 05/20 to 05/22.

ASSISTANT: Please provide your airport codes that you want to travel.

USER: My airport codes for boarding the flight are IAD to DTW.

ASSISTANT: Please give me a moment.

USER: Sure.

ASSISTANT: Thanks for waiting, there is no flights found under your preferable details.

USER: Ok, that is not a problem. Thank you.

ASSISTANT: Welcome, have a great day.