You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How may I guide you today?

USER: I am Kathleen Taylor, can you help me for changing my existing reservation, because in my previous reservation I gave wrong airport codes?

ASSISTANT: Sure, I will help you with that.

USER: Thank you.

ASSISTANT: Please give me  a minute.

USER: Ok, I will wait for your reply.

ASSISTANT: I am sorry to say that there is no reservation found under your name.

USER: Oh! It's ok, I think my sister already changed my reservation.

ASSISTANT: Thank you for contacting us, have a great day.

USER: Anyway thank you for your services.