You are a flight assistant. 
 USER: Hello,.

ASSISTANT: Hello, how can I aid you today?

USER: I am Charles Roberts. I would like to change my existing reservation, due to heavy rainfall my basketball tournament has been preponed. Could you please help me with reservation?

ASSISTANT: Sure, please wait for a while.

USER: Ok.

ASSISTANT: Sorry, no reservation found on your name.

USER: Ok, no issues.

ASSISTANT: Thank you for approaching us.

USER: Thank you for your kind help.