Can't update my iPhone to iOS 15
I can't update my phone with computer! It's not working about 1 day.
[Re-Titled by Moderator]
iPhone 12 Pro, iOS 14
Update your iPhone, iPad, or iPod touch
How to check the storage on your iPhone, iPad, and iPod touch
The iPhone needs Empty Space for the update to download, expand and then install.
If the iPhone does not have enough Empty Space - the update will fail and continue to fail until that issues is resolved.