You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello.

USER: I am Janet Garcia.

ASSISTANT: How can I help you?

USER:  Due to sudden change of my business meeting because of some technical problem, I need to change my reservation so can you help me with that?

ASSISTANT: Sorry, no reservation found by your name.

USER: That's ok, thank you.

ASSISTANT: Thank you.