You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am Ashley Walker.

ASSISTANT: How can I address you?

USER: My exams got postponed so I need to change my existing reservation. Can you please help me with that?

ASSISTANT: Sure, give me a minute. Sorry, there is no reservation found under your name.

USER: Ok, no problem. Thanks for your information.

ASSISTANT: Thank you for reaching us.