You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How can I help you?

USER: Stephen Evans here. Can you change my reservation?

ASSISTANT: Sure, I will help you with this.

USER: Thanks.

ASSISTANT: Stephen Evans, there is no active reservation found with your name in our database to change it.

USER: It's ok. Anyway, thank you for searching.

ASSISTANT: Thank you for contacting us.