You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you?

USER: I am Samantha Rodriguez. I want to change my existing reservation, as my trip planned with my friends has got postponed. Could you help me with it?

ASSISTANT: Sure, please wait a minute.

USER: Ok.

ASSISTANT: There is no reservation with your name.

USER: Ok, no problem. Thank you for your prompt service.

ASSISTANT: Thank you for reaching us.