You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you?

USER: I want to change my existing reservation due to bad weather condition, can you please help me with that?

ASSISTANT: Sure, please provide me your name to check your current reservation with us.

USER: My name is Edward Hernandez.

ASSISTANT: We have found reservation on your name, please share your airport codes.

USER: My source and destination airport codes are JFK and SEA.

ASSISTANT: May I know your travelling dates?

USER: I want to fly on July 14, return on July 16.

ASSISTANT: Do you prefer either economy or business class?

USER: I need an economy class flight ticket.

ASSISTANT: Do you have any specific airline preference?

USER: No.

ASSISTANT: Please wait for a while.

USER: Sure.

ASSISTANT: We don't have any flight available for the given route by you.

USER: Not an issue, thank you.

ASSISTANT: Thank you.