Same boat as me the first time I uninstalled and re-installed the game then it worked fine but I've had this problem at least 3-4 more times now. I even make separate saves in different locations at least 3 to try and avoid this issue but even doing that doesn't always work. Here's my other issue now sometimes and emphasis on sometimes it will load within 1-2mins but in my experience when it does your whole game is reset apart from your inventory. It just so annoying that I need to be this OCD about saving just so I don't lose my progress -.- anyway only fix I found were to reinstall the game, always make at least 2-3 save files FAR from your base preferably somewhere with not a lot of textures and objects, or to reload a slightly earlier auto save. The only other issue I have now is that my game takes 20mins to load but in a way its kinda good because when it does load at least I will know its working, if it loads too quick then you're game most likely reset.