You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How can I help you?

USER: I want to change my existing reservation. Can you help me for that one?

ASSISTANT: Sure, I am here to assist you. Please let me know your name.

USER: Sure, Anna Scott here.

ASSISTANT: Thank you. Please wait for a while, let me check your reservation status in our database.

USER: Sure.

ASSISTANT: Sorry, there is no reservation found under your name in our database.

USER: No issues, thank you for reaching us.

ASSISTANT: You are most welcome.