You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello,. How can I help you today?

USER: Please help me in changing my existing reservation, as my trip got postponed.

ASSISTANT: Sure, please can I have your name please?

USER: Carolyn Garcia here.

ASSISTANT: Sorry Carolyn Garcia, no flight reservation found with your given name.

USER: That's ok, no issues. Thank you.

ASSISTANT: Thank you for reaching us.