You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I help you?

USER: Margaret Harris here, I would like to book a ticket to Seattle for a business trip, so could you please help me with booking?

ASSISTANT: Sure, on which dates you are planning to fly?

USER: I am planning to go on 06/28 and please book a return flight also on 06/30.

ASSISTANT: Can you help me with your airport codes?

USER: Sure, I want to travel from DEN to SEA.

ASSISTANT: Thank you, please wait for a moment.

USER: Sure, I will wait for your response.

ASSISTANT: Thank you for waiting.

USER: No problem.

ASSISTANT: There is no flight on your requested dates.

USER: Oh, it's sad to hear.

ASSISTANT: Sorry for inconvenience.

USER: Anyways, thank you for the information.

ASSISTANT: You are welcome.