You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hi,.

USER: My name is Dennis Hall.

ASSISTANT:  How may help you ?

USER: I need your help in changing my recent reservation.

ASSISTANT: Sure Mr Dennis Hall , just a second .

USER: OK.

ASSISTANT: Mr Dennis Hall, I cannot find your reservation on your name .

USER: It's OK.

ASSISTANT: Thank you .