Last night Apple launched another update to iTunes. According to the release notes for version 12.5.3, there are some bug fixes and performance improvements. These are the exact same release notes as with 12.5.2, which was released a few days ago. This update likely brings a fix to an issue created with the last update.
To get the latest version of iTunes, you can go to the Mac App Store > Updates > Software updates > iTunes 12.5.3. If you’re on Windows, you can use Apple’s update utility to get the latest version. If you don’t have iTunes installed yet, you can download it from Apple’s website.