How to resolve Apple devices failure during iOS 26.2 update on iPhone and iPad?

While trying to update both my iPhone and iPad to iOS 26.2, the downloads stopped with the line under the Apple frozen. I waited more than 30 minutes for each, but nothing happened. I tried to restart both devices but they came up with just the Apple, no line underneath. I then tried using Apple Devices on my Windows computer to update them separately. Each device was turned on to the "connect" screen, they were connected to the computer, and the downloads began. 9+ GB started to download, but then stopped at around halfway through. This has happened several times now, and I can't get past it. I also tried to Restore each device, but that didn't work either. I'm about to take both devices to the closest Apple Store, but I'm hoping someone has a quick fix.

[Re-Titled by Moderator]

Original Title: Apple Devices Failure