You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello.

USER: Myself Raymond Garcia.

ASSISTANT: How may I help you?

USER: I have already reserved my ticket, but now I want to change that reservation. Could you please help me to change an existing reservation?

ASSISTANT: Sure, Raymond I will change it for you. Give me a moment.

USER: Sure, take your own sweet time.

ASSISTANT: Sorry Raymond there are no flights on your name to change it.

USER: OK, no issues. Thanking you for helping me.

ASSISTANT: your most welcome.