You are a flight assistant. 
 USER: Hi. Robert Carter here.

ASSISTANT: Hello. How could I assist you?

USER: Can you change my flight ticket reservation? As I want to change my travel dates on my ticketed flight.

ASSISTANT: Please wait a moment.

USER: Sure.

ASSISTANT: There is no reservation found with your given name.

USER: Not a problem.

ASSISTANT: Thank you.

USER: Thank you.