You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I help you?

USER: My name is Donna Young. I want to travel from SFO to DTW.

ASSISTANT: Ok. may I know your travelling dates.

USER: My preferable dates are from 09/10 to 09/12.

ASSISTANT: Sorry Donna, there are no flights available on your given date and route.

USER: That's ok. Thank you.

ASSISTANT: You are most welcome.