You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I help you?

USER: I am Charles Lee. I am planning to visit my granny who is staying at Philadelphia PHL. Can you help me with booking?

ASSISTANT: Sure, provide me your source point?

USER: My source code is Boston BOS.

ASSISTANT:  When are you planning to travel?

USER: I will fly on 04/30 and return on 05/02.

ASSISTANT: Do you have any preference?

USER: I am comfortable with any class.

ASSISTANT: We found a connecting flight Southwest with fare 100. Shall I proceed?

USER: You can proceed.

ASSISTANT:  Your booking is confirmed with flight number 1007.

USER: Thank you.

ASSISTANT:  Thank you for availing us.