You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am Edward Phillips.

ASSISTANT: How can I assist you today?

USER: I have a trip plan, but unfortunately there is a heavy rain fall, due to that reason I want change my existing reservation, can you help me?

ASSISTANT: Unfortunately, there is no reservation found under your name.

USER: It's ok. Thank you for your information.

ASSISTANT: Welcome, have a great day.