You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how best I can serve you at this moment?

USER: I need to change my existing reservation, Can you please help me with that?\.

ASSISTANT: Sure, we are here to help you.

USER: Thank you.

ASSISTANT: Please forward your name to check your reservation status in our portal.

USER: Rachel Miller here.

ASSISTANT: Ok, pleas be on hold.

USER: Sure.

ASSISTANT: Sorry, we hardly tried to find your reservation but, no reservation has been found on your respective name.

USER: Ok, no problem. Thanks for your information.

ASSISTANT: Thank you for approaching us with a query.