You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I amend you?

USER: I already have booked a ticket for my meeting but due to sudden change of dates, I need you to do some changes in my existing reservation.

ASSISTANT: Ok, please provide me your name to proceed further.

USER: Sure, my name is Emma Wright.

ASSISTANT: We found your reservation in our database, please provide me your upadated travel dates.

USER: Sure, my new journey dates are 04/16 and 04/18.

ASSISTANT: Let me know your source and destination please.

USER: I will board from Seattle WA-SEA and land on Denver CO-DEN.

ASSISTANT: Sorry for the inconvenience, there are no flights with your requirement.

USER: OK, no problem. Thank you.

ASSISTANT: Thanks for choosing us.