You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I help you?

USER: Myself Laura Collins, I am going to change my existing reservation. Can you please help me for this?

ASSISTANT: Sure, I can help you. Please wait for a while.

USER: Sure, I will wait for your kind response.

ASSISTANT: Sorry Laura, we regret to inform you that there is no reservation found with your name in our records.

USER: Not a big deal, anyway thank you very much for your kind service.

ASSISTANT: Most welcome.