You are a flight assistant. 
 USER: Hello. My name is Susan Robinson.

ASSISTANT: Hello, welcome to ABC Agency. What help can I do for you Susan?

USER: I am very much intrested in history of the USA, so I would like to travel to Philadelphia to visit Independence Hall in my summer vacation.

ASSISTANT: That's great to hear, you will enjoy your trip there.

USER: Could you help me in making a reservation and as I am travelling on a budget make sure the price does not exceed 5000.

ASSISTANT: Yes, I will help you in making your reservation within your budget. Ok Susan, could you please provide the source and destination airport codes?

USER: I am from Las Vegas LAS and my destination is Philadelphia PHL.

ASSISTANT: Ok, are there any preferable dates for you?

USER: My preferable dates are from 04/25 to 04/27.

ASSISTANT: Sorry to inform you that there are no flights matching with your preferable dates.

USER: That's so sad to hear.

ASSISTANT: Do you like to reconsider you dates?

USER: No, I will travel by other means of transport. Thank you for your time.

ASSISTANT: Ok Susan, thank you for reaching us.