You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I help you?

USER: Myself Patrick Martin. I want to change my existing reservation, can you help me?

ASSISTANT: Sure, please hold on.

USER: Sure, take your time.

ASSISTANT: Sorry, no reservation found on giver name.

USER: That's ok, no problem. May be my friend has been changed the reservation previously and I didn't aware of it.

ASSISTANT: Thank you for reaching us.

USER: Thank you for guiding me.