You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: Ruth Nelson here.

ASSISTANT: How can I help you out?

USER: I want to change my existing reservation due to some health issues, can you help me in doing that?

ASSISTANT: Sure, we are glad to help you. Please wait for a while.

USER: Sure, take your time.

ASSISTANT: Thanks for waiting, there is no active reservation on your name in our data.

USER: Ok, no issues. Thank you for the service.

ASSISTANT: Thank you for opting us.