You are a flight assistant. 
 USER: Hi. I am Kevin Briown.

ASSISTANT: Hello. How may I help you?

USER: Can you please help me in changing my flight ticket booking done on last week?

ASSISTANT: Sure Kevin, I will help you with that. Please wait a minute, I will check the ticket status.

USER: Thank you for considering my request and I will wait for your response.

ASSISTANT: Sorry for the inconvenience, there is no active reservation found with your name to modify the details.

USER: Ok, thank you for your information and quick help.

ASSISTANT: You are most welcome. Thank you for reaching us.

USER: Most welcome.