You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How can I help you today?

USER: I am Andrew Davis. I want to visit my grand mother's home on 10/28, so can you please book me a flight ticket on 10/27?

ASSISTANT: Sure, I am here to help you in booking. Could you please share your travelling airport codes?

USER: Yes, my airport codes are Minneapolis & St.Paul, MN-MSP and Denver, CO-DEN.

ASSISTANT: Please share your return journey date.

USER: Sure, I would like to return on 10/29.

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

USER: That's ok. Thank you for the response.

ASSISTANT: Thank you for reaching us, have a nice day.