You are a flight assistant. 
 USER: Hello. My name is Kimberly Smith.

ASSISTANT: Hello Kimberly. What can I do for you?

USER: All our family members are planning for a trip, but due to certain reasons, the trip is postponed. Could you help me in changing the existing reservation?

ASSISTANT: Sure, give me a moment, let me check your details.

USER: Ok.

ASSISTANT: Sorry, I didn't found any reservation basis on your details.

USER: That's ok. Thank you for your time.

ASSISTANT: Thank you, have a great day.