You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I assist you at this moment?

USER: Helen Rodriguez here. 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 this.

USER: Thanks for that.

ASSISTANT: Helen Rodriguez, there is no active reservation found under your name in our database.

USER: Anyway, thanks for the information.

ASSISTANT: Thank you for utilising our service.