You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hi,.

USER: I am Mary Martin.

ASSISTANT: How may help you?

USER: I would like to cancel my recent reservation due to my programme has shifted to another date. Will you please help me?

ASSISTANT: Sure I will help you definitely help you . May I know your name .

USER: I am Mary Martin.

ASSISTANT: I am sorry I  could not find any reservation on your name .

USER: OK, it's fine. Thank you for your help.

ASSISTANT: Thank you .