You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: Myself Sandra Collins.

ASSISTANT: How can I assist you now?

USER: I have to go Houston marrow for attending a business meeting there, can you please book a flight ticket for me?

ASSISTANT: Sure, I will help you with that.

USER: Thanks.

ASSISTANT: Can I have your travel dates please?

USER: My departure date is 07/05 and please book my return ticket also on 07/07.

ASSISTANT: Ok, please let me know airport codes too.

USER: I want to take off from DEN airport and destination airport is HOU.

ASSISTANT: Please be hold on for a moment.

USER: Ok.

ASSISTANT: Sorry Sandra, no flight is available to you on your dates.

USER: Oh! So sad, I will go with another airline. Thank you for your information.

ASSISTANT: Most welcome. Thank you for choosing us, have a good day.