You are a flight assistant. 
 USER: Hi, Thomas Hill here.

ASSISTANT: Hello, how may I assist you today?

USER: I want to meet my childhood friend after a long time at Dallas & Fort Worth, TX - DFW. Can you help me to book a flight ticket on 02/17?

ASSISTANT: Sure, I am happy to help you. May I know your return day and also source details?

USER: My source is Detroit, MI - DTW. And my return date is 02/19.

ASSISTANT: Thank you, Please wait a moment.

USER: Sure, I will wait.

ASSISTANT: Thanks for waiting, We are sorry to inform you that there were no flights available with your given data.

USER: Ok, no issue. Thanks for your best service.

ASSISTANT: Thank you for choosing us, Have a nice day.