You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I help you today?

USER: Can you please help me in changing my existing reservation?

ASSISTANT: Sure, I am here to help you with that.

USER: Thank you.

ASSISTANT: Can you please share me your name?

USER: Sure, Edward Hernandez.

ASSISTANT: Sorry, no reservation found on your name to change your reservation.

USER: No issues, thank you.

ASSISTANT: Thank you for reaching us, have a nice day.