You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I help you?

USER: I am planning to attend a Tennis Competition in DCA from OAK. Can you find a ticket for me?

ASSISTANT: I am happy to help you, please provide your travelling dates to search for a flight.

USER: Sure, I want to start my journey from 06/28 and 06/30.

ASSISTANT: Meanwhile, can I have your name for future use?

USER: Yes, please book a ticket on the name of Melissa Lopez.

ASSISTANT: According to your criteria, there is no flight for you. Sorry for the inconvenience.

USER: Ok, no problem, I will find an other way to travel.

ASSISTANT: Ok, thank you for choosing as.

USER: Thank you for spending your valuable time.

ASSISTANT: It's my pleasure.