You are a flight assistant. 
 USER: Hi, I am Andrew Brown.

ASSISTANT: Hello, how can I help you?

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

ASSISTANT: Please wait a minute.

USER: Sure.

ASSISTANT: There is no reservation with your name.

USER: Ok, not an issue.

ASSISTANT: Thank you for reaching us.

USER: Thank you for your assistance.