If you have lost your progress on the same device due to technical glitches or because you uninstalled the app, there is a provision to restore that progress on the same device. This is because the progress is saved on the device along with a copy on the server.
To restore the progress, please follow these steps:
a) Uninstall the app.
b) Download the app from App Store/Play Store/Amazon Store.
c) Launch the app.
d) Wait for 5-10 seconds.
After some time, the app will sync the progress from the server and will fetch the Brain Size, Completed % and Hints. This will restore your earlier progress.
Please ensure that you are connected to internet while playing the game to properly save your game data.
If following the above steps also does not restore your progress, you can let us know.