You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I assist you?

USER:  I am having sudden meeting in my office, can you please help me changing my reservation?

ASSISTANT: Sure, can I have your name please?

USER: Sure, my name is Angela Jackson.

ASSISTANT: There is no reservation found under your name to do modifications.

USER: No problem, thank you for helping me.

ASSISTANT: Thank you for choosing us.