Hi!
Encountered this with an iPhone 12 Pro, that updated to 14.7.1 via WiFi. We were able to solve it by updating to the latest Mac OS version [Latest Big Sur] plugging it to the Macbook Pro. And in Finder, clicking Restore iPhone. Before doing this I backed up all the photos and videos to the computer and also the contacts to ICloud.
The iPhone booted to it’s original welcome screen and cellular was already working with the icon showing a signal. It asked for passcode verifications, Apple ID. And tada it booted normally.
Mozartpena
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