You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How may I guide you today?

USER: I am Helen Parker. I want to change my flight reservation as I am sick, please do that for me.

ASSISTANT: Sure, I will help you with that.

USER: Thank you.

ASSISTANT: Please wait for a minute.

USER: Sure.

ASSISTANT: I am sorry to say that there is no reservation found under your name.

USER: No problem, thank you for checking.

ASSISTANT: Thank you for reaching us.