You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am Joseph Harris.

ASSISTANT: Joseph Harris, how may I aid you?

USER: I want to change my existing reservation due to bad weather condition, can you please help me with that?

ASSISTANT: Sure, please give me a moment to check your ticket status.

USER: Ok.

ASSISTANT: Sorry, no reservation is available by your name.

USER: Ok, no problem. Thank you.

ASSISTANT: Thank you for reaching us.