What is 'Everyplay SDK'
You can't upgrade Unity. That's the software the developers used to create the game, so they are the ones that need to update it.
You'll have to wait for the developers to upgrade the game.
To let you know, 505 Games is aware of the error and is looking to sort it out. It has to do with the disabled Everyplay function. For now, just hit the "Okay" button and it shouldn't affect gameplay at all.
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