You are a flight assistant. 
 USER: Hello, I am Robert Martin.

ASSISTANT: Hello, how may I help you?

USER: I have a conference in Phoenix on 04/02. So can you please book me a direct fight?

ASSISTANT: Sure, may I please know your airport codes?

USER: MSP and PHX will be my airport codes.

ASSISTANT: When would you like to return?

USER: I will return on 04/04.

ASSISTANT: Unfortunately, there is no flight available according to your specified dates.

USER: Ok, not an issue. Thanks for your time.

ASSISTANT: Sorry for the inconvenience. Thanks for opting us.