You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How may I help you out?

USER: I am Benjamin Miller. I would like to change my flight reservation as I am unwell, can you please help me?

ASSISTANT: Sure, I will help you in changing the ticket.

USER: Thank you.

ASSISTANT: Sorry, there are no reservations found.

USER: No problem, thank you for checking.

ASSISTANT: Thank you for reaching us.