The NHS COVID-19 app is designed to work with the official NHS QR codes only. The app will not recognise other QR codes.
Official QR code posters:
display the NHS Test and Trace or the NHS Wales Test, Trace, Protect logo
include the text 'Scan this QR code with your NHS COVID-19 app to check-in’ above the QR code
do not display any website URLs or direct you to a website when scanned