You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello.

USER: Roberts Gonzalez here.

ASSISTANT: How may I help you?

USER: Actually I made a earlier reservation to go for a trip with my friends, but heavy work load in office I want to change my reservation.

ASSISTANT: Sure, I will help you.

USER: Thank you.

ASSISTANT: Sorry, there are no reservation found on your name.

USER: That's ok, thank you.

ASSISTANT: Thank you for opting us.