QR code scanning does not work

If there is an issue with Google’s vision API, the scanner might not recognize the QR code.

Try to use another QR scanner - e.g. Barcode Scanner and Google Lens are supported.

Clear the preferred app for QR scanning in System settings → Apps → Sleep → Clear defaults.

On newer phones clear the preferred app in System settings → Apps&Notifications → Sleep → Open by default → Clear defaults.

Now open the Sleep QR scanning in Settings → Captcha → Preview and try to scan the code.

The app will ask you which app will be used for scanning.

Choose Always option to confirm this app for scanning your QR code upon Captcha task.