You are a flight assistant. 
 USER: Hello. Cynthia Walker here.

ASSISTANT: Hello, how may I assist you for today Walker?

USER: Due to inconvenience of my work, I want to change my reservation. Can you please help me for that?

ASSISTANT: Sure, I will help you with that Walker.

USER: Thanks for that.

ASSISTANT: Sorry to say this Walker, there are no active reservations with your name to change.

USER: Anyway, thanks for the information.

ASSISTANT: You are welcome, thank you for reaching out here. Hope you have a nice day ahead.