Saved files are not compatible between ZIsland UE4 and UE5 versions. If you want to play ZIsland v0.19 or higher or ZIsland Demo, please delete the "save folder" as previously commented
Thank you, I deleted the old version of the game and started the demo again :( There is no problem now, will there be problems when I get to that part? I wonder, but I don't think so :)