You are a flight assistant. 
 USER: Hello. I am Karen Thomas.

ASSISTANT: Hello, how can I serve you?

USER: Can you change my existing reservation as my exams got postponed?

ASSISTANT: Sure. Please, wait.

USER: Sure.

ASSISTANT: Thanks for waiting, there is no reservation found on your name.

USER: Ok, No issues. Thank you.

ASSISTANT: Thank you for reaching us.