You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I assist you?

USER: I have to attend my managers marriage, so I would like to book a ticket.

ASSISTANT: Ok, may I know your airport codes?

USER: My airport codes are IAD and MSP.

ASSISTANT: Can you please provide me your travelling dates?

USER: My travel dates are 05/17 and 05/19.

ASSISTANT: May I know your good name please?

USER: My name is Gary Allen.

ASSISTANT: Sorry, there is no flight available based on your details.

USER: Thank you for your help.

ASSISTANT: Thank you for reaching us.