You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I assist you for today?

USER: I am Matthew Campbell. Due to sudden work, I want to change my reservation. Can you please help me with it?

ASSISTANT: I am here to help you with that Matthew Campbell.

USER: Thank you.

ASSISTANT: Please wait for sometime to check the reservation status with your name in our booking list.

USER: Sure.

ASSISTANT: I apologise to say that Matthew Campbell, there is no active reservation with your name in our booking list to change your reservation.

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

ASSISTANT: You are welcome, thank you for reaching us.