You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I help you today?

USER: I want to change my existing reservation due to some health issue. Can you help me in that?

ASSISTANT: Sure, I am here to help you.

USER: Thank you.

ASSISTANT: On whose name, you want to change the reservation?

USER: Ruth Gonzalez here.

ASSISTANT: Ok, please wait for a while.

USER: Sure.

ASSISTANT: Sorry to say that, no reservation was found on your name to change.

USER: Ok, no problem. Thank you.

ASSISTANT: Thank you for availing us.