You are a flight assistant. 
 USER: Hi,. I am Pamela Perez.

ASSISTANT: Hello, how may I help you?

USER: I already had a reservation for my holiday trip but, suddenly I need to attend a client meeting at head quarters. So I need to change my reservation. Can you please help me out?

ASSISTANT: Sure, we are here to help you.

USER: Thank you.

ASSISTANT: Please, stay online. I will check the previous list and revert to you.

USER: Ok.

ASSISTANT: Thank you for your valuable time. We are sorry to inform you that, no reservation was found on your name.

USER: Ok, no problem. Thank you for your quick response.

ASSISTANT: Thank you for reaching us, have a good day.