You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello.

USER: Sarah Lopez here.

ASSISTANT: How may I help you?

USER: Can you change my flight ticket reservation? As my press conference has been postponed to some other dates.

ASSISTANT: Sure, please wait for a moment.

USER: Ok.

ASSISTANT: Sorry, there is no reservation found basis on your details.

USER: Ok, not a problem. Thank you.

ASSISTANT: Thank you for reaching us.