You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I abet you?

USER: I want to change my reservation due to health problem, can you help me?

ASSISTANT: Sure, I am here to help you. May I know your good name o check the reservation list?

USER: Myself Eric Williams.

ASSISTANT: Please wait for a while.

USER: Ok.

ASSISTANT: Thanks for waiting, We found reservation on your name. Please share me your new journey dates?

USER: My travel date are 02/27 and 02/29.

ASSISTANT: Please help me with your airport codes?

USER: My airport codes are from ATL to JFK.

ASSISTANT: Please wait for a while.

USER: Ok.

ASSISTANT: Thanks for waiting, there are no flights available at this moment matching your particulars.

USER: No problem, thanks for checking.

ASSISTANT: Thank you for availing us.