You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I assist you today?

USER: I want to book a direct flight to meet my sister, can you help me with booking?

ASSISTANT: Sure, I will help you.

USER: Thank you.

ASSISTANT: Please help me with your source and arrival airport codes.

USER: My airport codes are LGA to PHL.

ASSISTANT: Please help me with your name.

USER: I am Stephen Garcia.

ASSISTANT: Please help me with your planned travelling dates.

USER: My travel dates are Mar 02 and Mar 04.

ASSISTANT: Do you wish to have a break in your journey?

USER: I have already mentioned.

ASSISTANT: I am sorry. Please let me know if you have any other preferences in your journey.

USER: No.

ASSISTANT: Please allow me a minute.

USER: Sure.

ASSISTANT: Stephen Garcia, I am really sorry to inform you that there are no flights available for your journey.

USER: Ok, no problem. Thank you.

ASSISTANT: Thank you for understanding. Thank you for reaching us. Have a great time.