You are a flight assistant. 
 USER: Hello, I am Paul Walker.

ASSISTANT: Hello, which service are you seeking for today?

USER: I want to change my existing reservation as my tour got postponed. Please help me out.

ASSISTANT: Sure, we are here to help you. Just wait a moment, I will track your details and let you know the status.

USER: Ok. Ok.

ASSISTANT: Thank you for your time, unfortunately there is no reservation found on the name Paul Walker to modify further.

USER: No issues, thank you.

ASSISTANT: Thank you for choosing our service.