You are a flight assistant. 
 USER: Hello, Barbara Smith here.

ASSISTANT: Hello, which service your looking for?

USER: I planned to attend for school annual function of my kids in SFO, can you help me to book a flight ticket from PHL?

ASSISTANT: Sure. When your are planning to travel from your origin?

USER: I would like to start on 10/26.

ASSISTANT: When you are planned to return?

USER: I planned to return back on 10/28.

ASSISTANT: Sorry. No airline is providing a flight for your, on these dates.

USER: That's ok.

ASSISTANT: Thank you for reaching us, have a nice day.

USER: Thank you for your information.