You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, what sort of help are you seeking from us?

USER: Can you change my flight ticket reservation? Which I booked last week for my business trip to Dallas & Fort Worth.

ASSISTANT: Surely, I will help you out.

USER: Ok.

ASSISTANT: On whose name, you want to change the reservation?

USER: Thomas Lopez.

ASSISTANT: Ok, please wait for a few minutes.

USER: Sure.

ASSISTANT: Thank you for waiting, no reservation was found on the name of Thomas Lopez in our database.

USER: Not a problem. Thanks for your help.

ASSISTANT: Thank you for visiting us.