You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I address you?

USER: My plan to visit Minneapolis but due to my health issues I need to change an existing reservation. Can you please check the reservation by this name David Edwards?

ASSISTANT: Sure. Please wait a while. I will check and revert to you.

USER: Sure.

ASSISTANT: Thank you for waiting. Unfortunately there is no reservation found by that name.

USER: Ok, no issue. Thank you.

ASSISTANT: Thank you for approaching us.