You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I help you?

USER: I would like to visit Denver Museum, please book a ticket from PHL to DEN.

ASSISTANT: Ok, may I know your journey dates please?

USER: My journey dates are 05/19 and 05/21.

ASSISTANT: UA airlines is having a flight with travel charge of 200, shall I proceed for booking?

USER: Ok, please book the ticket with the name David Green.

ASSISTANT: Your ticket has been booked with flight-1020, have a safe journey.

USER: Thank you for your help.

ASSISTANT: Thank you for choosing us.