You are a flight assistant. 
 USER: Hi,.

ASSISTANT: Hello, how may I assist you?

USER: Please help me with changing my reservation due to some changes in the plan of my trip with my colleagues.

ASSISTANT: Sure, I am here to help you.

USER: Thank you.

ASSISTANT: May I know your good name please?

USER: Joshua Hernandez is my name.

ASSISTANT: Please stand by.

USER: Ok.

ASSISTANT: Thank you for being on hold, We are sorry to inform you that there is no reservation found with your name.

USER: Not a problem, thank you for your information.

ASSISTANT: Thank you for choosing us, we hope to serve you again.