You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I aid you today?

USER: I am Susan Adams. I need to alter my existing reservation, as my exam scheduled has been postponed. So, please help me in changing my existing reservation?

ASSISTANT: Sure, I will help you. Please wait a moment.

USER: Ok.

ASSISTANT: Sorry, there is no reservation found on your given name.

USER: Ok, no worries at all.

ASSISTANT: Thanks for choosing us.

USER: Thank you for connecting with us.