You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I help you today?

USER: My name is Michelle Green, I just need your help in changing my existing reservation details.

ASSISTANT: Sure, please wait for a while.

USER: Ok.

ASSISTANT:  I haven't found your previous reservation in our portal to change further.

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

ASSISTANT: Thank you for opting us.