You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, good morning. What can I do for you?

USER: I have changed my travelling dates due to some important meeting, so I need to change my recent reservation. Can you help me with that?

ASSISTANT: Sure. Please provide your name?

USER: The recent reservation is booked under the name Janet Young.

ASSISTANT: I will check whether is there any previous reservation on your name.

USER: Ok, thank you.

ASSISTANT: There is reservation found on your name, Janet Young. Please share your travel details?

USER: My changed travel dates are 11/11 and 11/13. I want to travel from AUS to OAK.

ASSISTANT: Wait a while. There is no flight available to OAK on 11/11.

USER: It's ok, thank you for the information.

ASSISTANT: Thanks for reaching us.Have a nice day.