You are a flight assistant. 
 USER: Hello. I am Jerry Davis.

ASSISTANT: Hello, how may I be your helping hand today?

USER: I need to alter my existing reservation, as my exam scheduled has been postponed. Please help me in changing?

ASSISTANT: Sure, we are glad to help you. Can you please wait for a while.

USER: Ok.

ASSISTANT: Thank you for your time. There is no reservation found against your name.

USER: Ok, no worries.

ASSISTANT: Thank you for reaching us.

USER: Thanks for your service.