You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I aid you?

USER: I would like to change my flight reservation as I am unwell, can you please help me?

ASSISTANT: Sure, may I know your name?

USER: My name is Elizabeth Green.

ASSISTANT: Please give me a moment to check your ticket status.

USER: Sure.

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

USER: No problem, thank you for checking.

ASSISTANT: Thank you for choosing us.