Hi how can i Download the New Update? 

if you click on the download file like you’re downloading it for the first time it’s an updated file

The download here on the itch page will always be the latest version you need. You can download it and drag+drop it on the https://play.date/account/sideload/ sideload page and it'll update your installed version (you may have to nudge the playdate to update it from the Folders section!)