You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I assist you?

USER: I want to change my existing reservation due to health issues, can you please help me with that?

ASSISTANT: Ok, may I know your name?

USER: My name is John Thompson.

ASSISTANT: Ok, please wait for a while.

USER: Sure.

ASSISTANT: Sorry, there is no active reservation found on your name to change.

USER: No problem, thank you.

ASSISTANT: Thank you for connecting with us.