How to fix iPhone 11 restart loop during iOS update?

I'm encountering a frustrating situation with my iPhone 11 while attempting to update to iOS 18.4. During the update process, I reached the screen where I'm prompted to enter my PIN code. After entering it, the phone begins to load the upgrade, but then it unexpectedly restarts and gets stuck in a looping restart mode. I've tried a few basic troubleshooting steps, like force restarting the device, but it hasn't resolved the issue. I'm seeking assistance or advice on how to get out of this cycle and successfully complete the update. Any help would be greatly appreciated!

[Re-Titled by Moderator]