You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello,. How may I help you?

USER: Please help me in changing my reservation with the name of Richard Anderson.

ASSISTANT: Sure, please be on hold.

USER: Ok.

ASSISTANT: Thank you for your time.

USER: Fine.

ASSISTANT: Sorry, we did not find any reservation in your name.

USER: No problem. Thank you for your service.

ASSISTANT: Thank you for reaching us.