You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello.

USER: I am Sharon Roberts.

ASSISTANT: How may I be of your helping hand?

USER: I would like to change my existing reservation, my family meeting has been postponed. Could you please help me?

ASSISTANT: Sure, please be on hold.

USER: Sure.

ASSISTANT: Thank you for your time. We are regret to say that, there is no any active reservation found in your given name.

USER: Ok, no issues at all. Thank you for your response.

ASSISTANT: Thank you for reaching us. Have a nice day.