You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am Catherine Collins.

ASSISTANT: How may I aid you?

USER: As my plans to visit Houston got postponed, can you please help me in changing my existing reservation to Houston?

ASSISTANT: Sure, we are here to help you.

USER: Thank you.

ASSISTANT: Please hold on a moment.

USER: Sure, I will wait for your response.

ASSISTANT: Sorry to inform you that there is no reservation found on your given name.

USER: Oh! That seems something went wrong while booking the ticket previously.

ASSISTANT: May be some times it happens.

USER: Thank you for providing information.

ASSISTANT: Thanks for reaching us, have a nice day.