You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello.

USER: Myself Jonathan Martin.

ASSISTANT: Martin, how can I assist you?

USER: Yes, for some personal reasons I want to change my reservation. Please help me out.

ASSISTANT: Sure. Let me check.

USER: Ok.

ASSISTANT: Sorry, no reservation found by your name.

USER: it's ok. Thank you for the information.

ASSISTANT: Thank you for reaching us.