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In the case of Android and i-Phone, your collected booster is stored in phone memory.This stored booster can not be synced with the server, because the game studio still does not have this process.You will not be able to transfer the boosters to another device, you will lose the complete booster for app uninstalling or crashing. And the boosters are not refundable.
I'm sorry, because I couldn't help you.😌
Here are some tips for not / less facing this kind of problem in the future,
Make your device software auto update.
Make your app auto update.
Don't open game when battery below 25%
Don't accept incoming call when you playing this game.
Close all background running app before start this game.
Make free device internal memory up to 2 GB
