You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I serve you?

USER: I am Richard Rodriguez. I would like to Change my existing reservation, due to heavy rains. Can you please help me?

ASSISTANT: Sure, We are here to help you. Please wait a while.

USER: Sure, I will wait for your response.

ASSISTANT:  Thank you for waiting, but I am sorry to say that, there is no active reservation found with your name in our database to change it.

USER: No problem, thank you for checking.

ASSISTANT: Thank you for picking us.