You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: Myself Katherine Taylor.

ASSISTANT: What can I do for you this evening, Taylor?

USER: I want to change my existing reservation as I do not want to travel in the airlines which I booked previously, I heard that airline is not providing good service, can you help me?

ASSISTANT: Ok, please wait for few seconds, I will check your existing reservation details to do modifications in that.

USER: Ok, take your time.

ASSISTANT: Are you sure you have booked the reservation with the given name only?

USER: Yes, I have booked on the name which I have mentioned previously.

ASSISTANT: But there is no reservation found under your name, Katherine Taylor.

USER: Ok fine, I think some thing went wrong while I was booking the ticket.

ASSISTANT: Yes, may be. Do you want any other help from us?

USER: No, thank you for your information.

ASSISTANT: It's my pleasure to serve you, thank you so much for utilising our service.

USER: Welcome.