You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. What help do you require from our agency?

USER: Would it be possible to change my recent reservation to new travel dates?

ASSISTANT: Sure, I am here to guide you in changing the ticket details. Can you please tell me your name?

USER: Ok, I am Mark White.

ASSISTANT: Ok, please give me a minute.

USER: Sure, take your time.

ASSISTANT: Sorry to inform you, there is no ticket booking found with your name to change the ticket details.

USER: It's ok, thanks for checking.

ASSISTANT: You are welcome. Thank you for opting us.