Sorry to hear you received an error. The only suggestion I have is to start your play from your last previously saved game. You may have to redo a few quests depending on how often you saved but it should work.
This suggestion is only good if you have been saving your progress, as many have suggested, by using different names such as - Simolia 1, Simolia 2, Simolia 3 and repeat or something of this nature. I have been saving my game after each completed quest just because I have a real life habit of save, save, save
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If you haven't been saving your progress using different names, then there is no way to undo the damage and you are just going to have to start from the beginning
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