You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello.

USER: I am Scott Roberts.

ASSISTANT: How can I serve you?

USER: I need to change my existing reservation, can you please help me with that?

ASSISTANT: Sure. Give me a minute.

USER: Sure.

ASSISTANT: Thanks for being waiting.

USER: Ok.

ASSISTANT: We didn't found any reservation by this name.

USER: Ok, no problem. Thanks for your quick response.

ASSISTANT: Thank you for reaching us.