How to Fix Unable to Scan QR Code on iPhone Camera [easy]

The quickest fix for an iPhone camera not scanning a QR code is to check and re-enable the dedicated setting, which is often the cause of the problem. Simply go to your iPhone's Settings, scroll down and tap on Camera, and ensure the Scan QR Codes toggle is switched on (green); if it's already on, turn it off, wait 30 seconds, and turn it back on, which often resets the feature and gets it working again, but if the issue persists, you should force-quit the Camera app or restart your iPhone.