You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello.

USER: I am Sandra Hall.

ASSISTANT: How can I assist you?

USER: Can you help me to book a flight from DCA and MSP?

ASSISTANT: Sure Hall, can I know the travel dates please?

USER: My trip dates are 03/10 and 03/12.

ASSISTANT: Ok, wait a moment please.

USER: Sure.

ASSISTANT: Sorry, there are no flights available on your dates.

USER: Ok, no issues. Thank you for your help.

ASSISTANT: You are welcome.