You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: My name is Jonathan Jackson.

ASSISTANT: How may I assist you today?

USER: I want to change my existing reservation. Can you please help me for that?

ASSISTANT: Sure. But I did not found any reservations with your name.

USER: It's ok, thank you for your information.

ASSISTANT: It's my pleasure Jonathan Jackson.