You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I help with our services?

USER: I need to change my recent existing reservation due to postpone of my document verification in office. Help me in changing my recent reservation with the name Gary Johnson.

ASSISTANT: Ok, I can help your better. Please wait a moment, I will check the status of your reservation and let you know.

USER: Sure, I will wait for your response.

ASSISTANT: Thanks for waiting, but we did not find any active reservation on your name.

USER: Its ok, thank you for your assistance.

ASSISTANT: Thanks for consulting us, hope to serve you better next time.