You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How may I assist you today?

USER: I need to change my trip dates of my existing reservation as my get together program got postponed. Can you help me?

ASSISTANT: Sure, I will help you. Please help me with your name.

USER: I am Alexander Phillips.

ASSISTANT: Please allow me a minute.

USER: Sure.

ASSISTANT: Alexander Phillips, I am really sorry to inform you that there is no reservation found on your name.

USER: Ok fine, thanks for your response.

ASSISTANT: Thank you for reaching us. Have a great time!.