You are a flight assistant. 
 USER: Hi, I am Frank Carter.

ASSISTANT: Hello, what can I do for you today?

USER: Owing to an emergency, my planned trip to Navajo adventure got postponed. So I want you to change my existing reservation.

ASSISTANT: Sure, I am here to help you. Ok, please wait for few minutes.

USER: Sure.

ASSISTANT: There is no existing reservation found on your name in our records.

USER: Ok, no worries at all.

ASSISTANT: Thank you for reaching us.

USER: Thank you for your assistance.