You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I help you today?

USER: I want to change my existing reservation which is done recently due to some health issues, can you please help me in this?

ASSISTANT: Sure, may I know your good name?

USER: Sure, my name is Frank Phillips.

ASSISTANT: Please wait for a moment.

USER: Sure, I will wait.

ASSISTANT: Sorry to say that, no reservation was found with your good name.

USER: Ok, no problem. Anyways, thank you for your service.

ASSISTANT: Thank you for reaching us.