It’s unclear just how many new iPhone 12 owners are affected, but it seems that there’s at least some kind of issue that prevents the new iPhones from consistently recharging on a wireless charger.
The problem appears to predominantly affect those using Qi-based chargers, rather than Apple’s MagSafe chargers, but I haven’t seen enough evidence to rule out the latter yet. The problem is simple: When you slap your iPhone 12 on your Qi charger, nothing happens. No charging takes place, and no amount of fussing with your iPhone placement on said charger makes it work.
According to 9to5Mac, Apple is aware of the issue and is allegedly working on a fix. That’s good to hear, because it doesn’t sound like there’s a hardware issue that you might need to address by shipping your iPhone 12 off to Apple (or taking it into a retail store). The bad news is that you’re going to have to be patient, because there’s no estimate for when this official fix might arrive. In the meantime, there are a few steps you can take to troubleshoot this issue yourself.
First, and most importantly, get calm. I wouldn’t contact Apple to replace my iPhone—requiring you to set it all up again from scratch (or a backup). Nor would I reset my iPhone (via Settings > General > Reset > Erase All Content and Settings) in the hopes that will address the issue, as that’s a bit of a thermonuclear approach to the problem that isn’t guaranteed to fix it.
Make sure you’re running iOS 14.2, as it specifically fixes some issues that previously prevented devices from charging wirelessly. If that doesn’t help you out, I have seen reports that people are able to get their iPhone 12s charging again by performing a Force Restart whenever they encounter the wireless-charging bug: Press the Volume Up button, then press the Volume Down button, then hold the Side button (the one you use to turn your iPhone 12's screen on and off). Once you see the Apple logo appear, release the Side button and wait for your iPhone to restart.
You can also switch to a wired charger for the time being if you’re tired of your iPhone having less battery when you wake up than when you went to sleep. That’s complicated a bit by the fact that the iPhone 12s didn’t come with power adapter—just a cable. Here’s hoping you have some kind of USB-C adapter (or computer) sitting around. If not, it’s time to bug a Apple-loving friend to let you borrow one of the 8 different power adapters that are probably sitting in one of their desk drawers.