I was playing castle cats and after downloading the update all my progress was gone. So in order to preserve my progress I have to log in Google play but it won't let me login. It keeps saying there is an error. I tried in other apks and the same happened. It won't let me login. However, it does let me login when I download the game from the play store
Try to download the game directly from Google play store instead of using apk. Some game required you to do so as they usually check from where you obtain the game
Best soulution is just start over as u have an moded game from here it will take a few min to get to the point u are now, most moded games/apps wont let u login with ur google acc, some might have facebook login , but then again u need to uninstall ur facebook app from ur mobile then login with facebook credentials in the game/app after that u can redownload ur facebook app.
A lot of modded games will not allow you to log in because to create the mod you have to separate it from the google play integration. Depeding on the game, save data might be in a folder on your device. If you can't find it there, a helium save may be an option too.
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