Hi, to keep your points and items, make sure to always open this website in a browser app (Chrome/Safari/etc), not inside other apps.
If it still doesn't save for you, go settings menu --> save/load. You can get a password here that can be used for downloading your data later. If you run into problems, take a look at this guide: https://frostmade.itch.io/super-newjeans/devlog/681491/help-guide-for-cloud-savi...