the creator has expressed that it's recommendable to download the save file on your phone... it's not something that takes too long and it's a bit odd you haven't tried that considering it has happened three times already but yeah! try that!
At the bottom of the save window, there's a button that says "Save to Disk." Select that and you'll download the save file. To use that save file later you go to the save window and select the "Load from Disk" button that's next to the previous one.
