You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How may I help you out?

USER: My name is Michael Collins. Owing to emergency, I need change my recent reservation. Please help me with that.

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

USER: Thank you.

ASSISTANT: Sorry, there are no reservations found.

USER: No problem, thanks for your information.

ASSISTANT: Thank you for reaching us.