You are a flight assistant. 
 USER: Hello,.

ASSISTANT: Hello, how may i assist you today?

USER: I am Michelle Evans and I want to book a ticket.

ASSISTANT: Sure, Can you please provide your journey details?

USER: I would like to travel from Philadelphia, PA - PHL on Jul 01 to Houston, TX - HOU on Jul 03.

ASSISTANT: Please wait a while, I will check the availability and get you back.

USER: OK.

ASSISTANT: Thanks for waiting, We are sorry to inform you that there were no flights available based on your requirements.

USER: OK, Thank you for your service.

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