You are a flight assistant. 
 USER: Hello, I am Jeffrey Brown.

ASSISTANT: Hello. How can I assist you?

USER: I want to postpone my existing reservation due to an emergency. Can you aid me in ding some changes in my existing reservation?

ASSISTANT: Sure, let me check your reservation status in our database.

USER: Take your time.

ASSISTANT: Sorry, there is no reservation found in our database.

USER: No issues. Thank you for checking.

ASSISTANT: Thank you for reaching us.