You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, How can I aid you?

USER: I want to change my existing reservation which is done recently due to some problems, can you please help me?

ASSISTANT: Sure, I will help you.

USER: Thank you.

ASSISTANT: May I know your name?

USER: Sure, my name is Larry Green.

ASSISTANT: Please wait.

USER: Sure.

ASSISTANT: Thanks for waiting.

USER: My pleasure.

ASSISTANT: There is no reservation on your name.

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

ASSISTANT: Thank you.