You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I aid you?

USER: Owing to an emergency, my scheduled trip with my friends  to Washington has been postponed. So I want you to change my existing reservation?

ASSISTANT: Sure, may I know your good name please?

USER: Sure, I had a earlier reservation with name Rachel Allen.

ASSISTANT: Ok, please wait a moment.

USER: Sure.

ASSISTANT: Thank you for being wait. Unfortunately there is no reservation found with your name.

USER: Ok, no worries at all. Thanks for your assistance.

ASSISTANT: Thank you for approaching us.