I'm so glad that you're enjoying this! And thank you for reading
Do you mean saves to your browser (hitting save and then just clicking one of the numbers slots)? Because those get erased when removing cookies or clearing out a browser session (as far as I know). In order to prevent that, when you hit save, go down to the bottom of the save window where it says "Save to Disk". This will save it to your actual device. Next time when you start the game, just go to the saves and hit "Load from Disk", this will give you the option to select the save from your files. (For me, my saves usually go into my downloads folder.)
(And as far as I know, it's not possible to get the saves back. I'm sorry.)