You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I aid you?

USER: Can you please help me with changing my recent reservation?

ASSISTANT: Ok, please provide me your name to proceed.

USER: My name is Sandra Lopez.

ASSISTANT: Ok, please can you with a moment I will check?

USER: Ok.

ASSISTANT: Thank you for waiting, sorry as per your concern I can not amend the reservation because it is not found in our records of reservation.

USER: That's ok. Thank you.

ASSISTANT: Thank you for choosing our agency.