You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How may I help you?

USER: I am Jeffrey Wilson. I am planning to travel from DTW to SFO, can you help in booking?

ASSISTANT: May I now your travel dates?

USER: My travelling dates are 05/18 to 05/20.

ASSISTANT: Sorry, there is no flight found basis on your details.

USER: That's ok, thank you for your help.

ASSISTANT: Most Welcome.