You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How can I assist you today?

USER: I need to reschedule my trip dates due to my leaves are not approved. Can you help me in change an existing reservation?

ASSISTANT: Sure, I am here to help you. Please provide me your name.

USER: I am Emma Roberts.

ASSISTANT: Ok, please wait for a while.

USER: Ok.

ASSISTANT: Sorry Emma, I did not find any reservation by your name.

USER: Ok, not an issue. Thanks for your information.

ASSISTANT: It's my pleasure.