You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, How can I help you?

USER: My name is Jack Phillips. I want to travel from San Francisco, CA - SFO on 12/26 to attend my sister in law's birthday party. Can you help me book a flight ticket to Detroit, MI - DTW.

ASSISTANT: Sure,May I know the destination and return date?

USER: I will return on 12/28.

ASSISTANT: Sorry to tell that there is no flight  found on your requirements.

USER: Ok, thank you for your response.

ASSISTANT: Thank you for approaching us.