You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I aid you?

USER: I am Catherine Lewis. I need modify my reservation due to some issues, can you help me out please?

ASSISTANT: Sure, give me a minute.

USER: Sure, take your own time.

ASSISTANT: Sorry, there is no reservation found under your name.

USER: That's ok, no problem. Thank you for your help.

ASSISTANT: Thank you for choosing us.