You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, do you need any help from us?

USER: I would like to change my recent reservation, will you help me with that?

ASSISTANT: Sure, could I have your name please?

USER: Thank you for accepting my request. Myself Melissa Moore.

ASSISTANT: Ok, please allow me a moment.

USER: Ok, I will wait.

ASSISTANT: Sorry, there is no reservation with your name in our portal to make changes further.

USER: Ok, not an issue. Thank you for your information.

ASSISTANT: You are welcome, have a great day.