You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I best aid you now?

USER: I am Andrew Robinson. Due to my health problem I want to change my reservation, can you please help me that?

ASSISTANT: Sure, we are here to help you.

USER: Thank you.

ASSISTANT: Please wait for a moment.

USER: Ok, I will wait for your response.

ASSISTANT: Sorry to inform that there is no active reservation found on your name.

USER: Ok, no problem. Thank you so much.

ASSISTANT: Thanks for reaching us, wish you a good day.