I’ve figured out why the blog layout page turns from masonry to normal without any reason. It’s because I had activated the Blog page as “post page” inside Appearance- customize. There I had set a static page (home) and the post page (blog) When I did that, it changed the layout without advise. If you change it back, it goes back to masonry layout, so I hope I can work with it, I just though you’d like to know in case it happens to someone else 🙂
Thank you for everything!