You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I help you?

USER: Myself Stephanie Hernandez.

ASSISTANT: Ok.

USER: I want to change my existing reservation, can you please help me for that?

ASSISTANT: Sure, I will help you in changing your reservation.

USER: Thank you.

ASSISTANT: Sorry, no reservation found with your name.

USER: That's ok, thank you for checking.

ASSISTANT: Thank you for reaching us.

USER: Welcome.