You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you?

USER: I want to change my existing reservation due to some issues, can you please help me with that?

ASSISTANT: Sure, can you provide me with your name please?

USER: Sure, I am Rachel Rodriguez.

ASSISTANT: Please give me a moment.

USER: Sure.

ASSISTANT: Rachel Rodriguez. I regret to inform that there is no reservation by your name.

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

ASSISTANT: Thank you for reaching us.