You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello.

USER: I am Mary Harris.

ASSISTANT: How can I help you?

USER: I want to change my reservation, can you help in that?

ASSISTANT: Sure, give me a minute.

USER: Sure.

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

USER: That's ok, thank you for your help.

ASSISTANT: Thank you for opting us.