What's wrong with updating ios11 not letting it download? How do I fix it?

After the Control Center toggles the Wi-Fi switch, the device immediately disconnects from the Wi-Fi network, but features such as Continuous Connectivity (e.g., Handoff and Instant Hotspot), location-based services, AirDrop, and AirPlay still work, AirDrop, and AirPlay will still work.

Control Center toggles Bluetooth on and off, and the device immediately disconnects Bluetooth-connected accessories, but official accessories like the Apple Watch and Apple Pencil still work.

iOS 11 is an operating system developed by Apple. At 1:00 am Beijing time on June 6, 2017, the Apple developer conference WWDC 2017 was held at the McEnery Convention Center in San Jose, California, and Apple's system iOS 11 was officially unveiled.

The official version of iOS 11 in September 2017 with the release of new iPhones to push the update upgrade.

On September 20, 2017, the official version of iOS 11 was released, adding specific features such as QR code scanning, fraudulent text message recognition, pinyin keyboard, and Shanghainese voice recognition. on September 26, a week after the release of iOS 11, Apple released the upgrade package and the latest version of the system iOS 11.0.1 to the public, the new version is designed to fix the previous version of the existence of various software issues.