You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I assist you?

USER: I am Stephanie Moore, planning to visit San Francisco. Can you please book me a ticket from PHL to SFO?

ASSISTANT: Ok, can you please tell me your travelling dates for this journey?

USER: My preferable journey dates are from 12/15 to 12/17.

ASSISTANT: Stephanie Moore, please wait for a while.

USER: Sure, I will wait for your response.

ASSISTANT: Sorry, I can not find any flights for your journey.

USER: Ok, not an issue. Thank you for providing information.

ASSISTANT: Thank you for choosing our services.