You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I help you at this moment?

USER: Please change my existing reservation which I have done with my name Donald Hernandez.

ASSISTANT: Sure. Please wait for a moment. I have found your reservation, please let me know your journey dates.

USER: Sure, my airport codes are from IAH to CLT.

ASSISTANT: Ok.

USER: My travelling dates are from 09/23 to 09/25.

ASSISTANT: Can you please share the dates? Ok, please let me check.

USER: I need 1 connected flight. Ok, take your time.

ASSISTANT: I found a connecting flight with Delta airline, shall I book it?

USER: Ok, please proceed.

ASSISTANT: Your booking is done with flight number 1003. Happy journey.

USER: Thank you.

ASSISTANT: Welcome. Thank you for reaching us.