You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: Jessica Turner, here.

ASSISTANT: How can I help you now?

USER: I want to change my existing reservation due to heavy rain fall in JFK.

ASSISTANT: Ok, please wait for a moment.I will check the details. Sorry Jessica, there is no reservation found on your name.

USER: It's ok, thank you for your help.

ASSISTANT: You are welcome, have a nice day.