Open the Camera app on your iPhone
Point the camera at the QR code on the screen
Wait for the notification to appear
Tap the notification to open the link or action
If the QR code is on the same iPhone screen, take a screenshot first
Open the Photos app
Open the screenshot containing the QR code
Press and hold the QR code, or tap the QR code detection option if shown
Tap the link or action that appears
If needed, use the Control Center
Add the Code Scanner if available
Open Code Scanner
Scan the QR code displayed on the screen
If the QR code is too small, zoom in on the screen
Increase screen brightness if needed
Clean the camera lens if the code is not detected