A game crash is usually caused by a lack of memory on your device.
Before taking any other steps, make sure that your game is updated and that the device you're playing on is of the minimum specification needed to run the game smoothly. A full list of supported devices can be found in this help center under the article heading 'What devices are compatible with Legend of Solgard?'.
If you've checked the list and the device is of minimum specification and up-to-date, the next bext step is to restart your device which clears the memory and don't worry this will not cause any loss of data.
Make sure you've recently connected your game to the Game Center or Google Play Games to synchronise your progress before reinstalling the game.
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