You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How can I assist you today?

USER: My friend is giving a presentation on national competition in PHL, but due to some sudden changes, I want to change my existing reservation.

ASSISTANT: Sure, I will help you with that. Please give me a moment.

USER: Please check my flight ticket with name Cynthia Scott.

ASSISTANT: Sorry Scott, there is no reservation has found under your name.

USER: Ok, fine.

ASSISTANT: Thank you for choosing us.

USER: Thank you for your fast service.

ASSISTANT: Most welcome.