iOS 15.1 download error on iPhone 13 pro

I don't know what kind of error is showing up, but force reset is worth a try:

https://support.apple.com/en-gb/guide/iphone/iph8903c3ee6/ios

"To force restart iPhone X, iPhone XS, iPhone XR, iPhone 11, iPhone 12, or iPhone 13, do the following:

Press and quickly release the volume up button, press and quickly release the volume down button, then press and hold the side button. When the Apple logo appears, release the button."

Try updating after that, make sure You are connected to WiFi network before the update. Hope it will help :)

I’m so glad I found this thread! The exact same thing kept happening to me on an iPhone 13 Pro, as shown in the photo. But after seeing your experience here, I also force-reset it multiple times and voilà, downloaded and updating now! (I had already force-reset it once, but when that didn’t do it, I came here for help. So glad I did 🙏 )

I had the same error 3x times even after I hard booted the iPhone 13 Pro.

Then I synced it with my MacBook Pro and checked for update on the sync screen on my MacBook Pro. Then did the download and update via my laptop and it worked OK.