You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I help you today?

USER: Steven Lopez here. I want to change my existing reservation. Can you help me in that?

ASSISTANT: Sure, I will be helping you with the request, please wait a moment.

USER: Ok.

ASSISTANT: Sorry, there are no active reservation to change your trip.

USER: Ok, not an issue. Thank you for giving information.

ASSISTANT: Thank you for reaching our service.