You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: Raymond Jackson here.

ASSISTANT: How may I assist you?

USER: I would like to spend some more days with my family, please help me in changing my existing reservation.

ASSISTANT: Sure, I will help you in that.

USER: Thank you.

ASSISTANT: Please wait for a while.

USER: Sure, take your time.

ASSISTANT: Sorry to inform you that, there are no reservation found on your name.

USER: Ok, no problem. Thank you for your information.

ASSISTANT: Thanks for reaching us.