You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, welcome to AS agency.

USER: Benjamin Smith here.

ASSISTANT: How can I assist you, Smith?

USER: Actually my friend got married recently at DEN and invited me to lunch from HOU, can you please help me in booking a ticket?

ASSISTANT: Surely I will help you with that, may I know your planned journey dates?

USER: My dates of journey starts from 04/10 and ends at 04/12.

ASSISTANT: Fine, give me few seconds to check the availability of flights on those dates.

USER: Ok.

ASSISTANT: There are no flights available on those dates, do you want to try in some other dates?

USER: No, we didn't planned as of now. Thank you for your help.

ASSISTANT: That's ok, thank you for choosing us. Have a great day.

USER: Welcome.