You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I assist you today?

USER: I want to change my brother's reservation, as he booked a flight on the wrong route. Can you help me?

ASSISTANT: Sure, I will help you with that.

USER: Thank you.

ASSISTANT: Can I have the name on which ticket has reserved earlier?

USER: My brother's name is Dennis Johnson.

ASSISTANT: Ok, please wait a moment.

USER: Sure, take your time.

ASSISTANT: Sorry, there is no reservation found under the name of Dennis Johnson.

USER: Oh! Maybe he already changed his reservation and did not inform me.

ASSISTANT: May be.

USER: Anyways, thank you for checking.

ASSISTANT: My pleasure. Thank you for choosing us, have a great day.

USER: You are most welcome.