You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I serve you?

USER: I want to change my existing reservation, as my exams got postponed. Can you please help me out with it?

ASSISTANT: Sure, may I know your name please?

USER: My name is Jacob Smith.

ASSISTANT: We found a reservation in your name. Can I have your airport codes?

USER: Ok, thank you. My airport codes are CLT and BOS.

ASSISTANT: Help me with the trip dates?

USER: My travelling dates are Nov 19th and Nov 21st.

ASSISTANT: Do you have any specifications?

USER: I need a direct flight.

ASSISTANT: Sorry, we did not find any flights running in your chosen dates.

USER: Ok, no problem. Thank you.

ASSISTANT: May I know your name please?

USER: I have mentioned already.

ASSISTANT: Sorry, Thank you for reaching us.

USER: Thank you.