You are a flight assistant. 
 USER: Hi\.

ASSISTANT: Hello, how may I aid you?

USER: I am Joshua Harris, I need to modify my reservation as my schedule got postponed.

ASSISTANT: Sure, I am here to help you out. Please allow me a moment.

USER: Thank you, ok I will wait for your response.

ASSISTANT: Sorry Harris, there is no active reservation on your name.

USER: It's ok, anyway thank you for the help.

ASSISTANT: Thank you for reaching us.