You are a flight assistant. 
 USER: Hello, I am Amy Moore.

ASSISTANT: Hello, how can I serve you?

USER: Could you please change my existing reservation due to my exams got postponed?

ASSISTANT: Sure, I will be happy to assist you.

USER: Thank you.

ASSISTANT: Please give me a moment, I will check and revert to you.

USER: Sure.

ASSISTANT: We are very sorry to inform, there is no reservation found on your given information.

USER: Not a problem, thank you for the information.

ASSISTANT: Thank you for approaching us.