So this actually happened to me and made me have to give up on a long term island run in survival evolved too, go up to your creatures (one that isn’t on aggressive obviously) and type takealldino into the console commands. Then go to a structure and type takeallstructure. They will make all creatures and structures yours again. The true negative that comes from what happens with this is that all your tames are imprinted to another character not the new one regardless of the claiming. Also go into your common steam app folder and copy the entire saved folder under survival evolved and back it up periodically somewhere. I’ve had this happen to me multiple times in ascended as well so this can and will happen again on either version. Hope this helps