You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, do you need any help from us?

USER: I am Thomas Mitchell. I want to change my reservation as I am sick, can you please help me?

ASSISTANT: I have found reservation, can you please tell me your departure and arrival day?

USER: Sure, I want to depart on June 25 and I will return back on June 27.

ASSISTANT: Ok, may I know your location airport codes?

USER: Yes, I will travel from LAX to DCA.

ASSISTANT: The economy class with flight number 1000 of JetBlue airline is available having connection as 1, is it ok for you?

USER: Yes, it's ok for me. Please book the ticket.

ASSISTANT: Ok, your reservation is confirmed.

USER: Thank you very much for your help.

ASSISTANT: You are welcome, have a great day.