You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How can I assist you?

USER: I am planning for a holiday trip with my friend's, but due to some urgent work it has been postponed.So I would like to change my existing reservation. Can you please aid me in changing my existing reservation?

ASSISTANT: Sure, can I know your name please?

USER: Ronald Jones here.

ASSISTANT: Sorry, there is no reservation found on your name.

USER: Ok, no worries at all.

ASSISTANT: Thank you for approaching us.

USER: Thank you for your response.