You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How may I assist you today?

USER: Could you please change the reservation on the name of Sandra Campbell?

ASSISTANT: Please wait a moment, let me check with your details.

USER: Sure, make it fast.

ASSISTANT: Sorry, there are no reservations found on your given name to change.

USER: Not a problem, thank you for your information.

ASSISTANT: Thank you for reaching our service.