You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: Donna Anderson here.

ASSISTANT: How may I assist you?

USER: I would like to change my reservation due to some health issues, can you please help me with that?

ASSISTANT: Sure, I am here to help you out.

USER: Thank you.

ASSISTANT: Wait a moment please.

USER: Sure, I will wait for your response.

ASSISTANT: Donna Anderson , we haven't found any reservation under your name in our database.

USER: That's ok, no problem. Thank you for checking out.

ASSISTANT: Thank you for reaching us.