You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I help you today?

USER: I want to change my reservation, due to some problems I am unable to travel those dates, can you please change my reservation?

ASSISTANT: Sure, I will help you with that. Please wait for a minute.

USER: Thanks.

ASSISTANT: May I know your name please?

USER: Sure, my name is Sharon Robinson.

ASSISTANT: I am sorry to say that there is no reservation found.

USER: Oh! It's ok no problem. Thank you for your information.

ASSISTANT: Thank you for contacting us.