On the Bedrock Edition

The file size before the release of 1.12 was around 500MB ish, but now when I download it, its about 80 MB and when I play the file, none of it is saved and the world is reset while the realm stays fine. This is frustrating as I use the downlaod feature for backups and to mess around on. Please look into this. It worked fine before and only started happening since the game updated.