You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How can I assist you at this moment?

USER: Can you please help me in changing my recent reservation?

ASSISTANT: Sure, I am happy to help you with that.

USER: Ok.

ASSISTANT: Can I have your name please for checking your reservation status?

USER: Myself Jonathan Mitchell.

ASSISTANT: Ok, please wait a moment.

USER:  Ok.

ASSISTANT: Yes, I have found your reservation so please let me know airport codes of your new locations.

USER: My source is IAD and destination is PHL.

ASSISTANT: Can I have your travel dates please?

USER: My trip dates are 09/05 to 09/07.

ASSISTANT: Please wait for a second.

USER: My travelling dates are 09/05 and 09/07. Ok.

ASSISTANT: Sorry Jonathan Mitchell, no flight is available to you on your dates.

USER: Ok, fine thank you for checking.

ASSISTANT: Thank you for choosing us, have a good day.