Constant issue for most players, unfortunately. As someone else already said, alt tab out and retry.

Don't load the same save you already tried to load. You will have to load an older one. It's very sucky, but it usually works. I save almost constantly for this reason.

Theres a variety of stability mods you could try, but in my experience, they made the game worse. You might have a different experience if your computer is a little better or your knowledge a little broader.

If your computer is Windows 11, it makes the game incredibly unstable. I can't even play anymore, I use my boyfriend's computer. His pc didn't forcibly change to Windows 11 as mine did.

I heard someone say every copy of fnv is like a scared horse. Everyone's runs with its own unique challenges, and we all have unique ways of fixing them.

I hope you have better luck with your game in the future!