world loading issue

I turned my hardcore world into spectator after I was needing to take a picture for a sketch, but I left accidentally before I was able to go back to survival, and ever since then, my world gets stuck on "loading terrain" and I can't open it anymore. All of my other worlds work perfectly fine, even the other hardcore worlds that Ive died in. I tried everything and have even backed up the world and reloaded it. Still nothing.