You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, what can I do for you today?

USER: I want to change my existing reservation due to my bad health issues. Can you help me in doing that?

ASSISTANT: Sure, I will help you.

USER: Thank you.

ASSISTANT: May I know your name please?

USER: Sure, Kimberly Collins here.

ASSISTANT: Thanks for your name, please wait.

USER: Sure, I will wait for your response.

ASSISTANT: Thanks for your time, we could not find any active reservation on your name to change.

USER: Ok, not an issues. Thank you for your effort.

ASSISTANT: Thank you for selecting us.