Glad to hear you're enjoying the game, sorry for the issues!I'm not so sure why this started happening, as of recently. I cannot create and load saves. Re-downloading the game did not work either.
Also when opening up the game after a day or two it's throws errors when engaging in sex scenes. I'll see if I can get the correct error code but it said something about ”error in A-track”
I'm playing on JoiPlay. Has worked before on the same device, Pixel 7A, either way it's a fantastic game. Been playing for about a year now.
X-Change Life stores save data in your browser's local storage. So if your local storage is full for any reason, that can inhibit's the game's saving capability. Unfortunately I don't know much about JOIPlay, but if you can (first exporting the save to a file) clear the browser cache somehow, you may be able to clear enough space to save the game.