Why is the QR check in poster not working?

- Should the QR code poster not be working, the first thing to try would be to clear the device's cache

1. Open the Chrome app
2. Tap the three dots (More) icon in the top-right corner
3. Select Settings, then Privacy and security
4. Tap Clear browsing data
5. Choose a time range and the specific data you want to delete (such as "Cached images and files")
6. Tap Clear Browsing Data

1. Open the Firefox app
2. Tap the hamburger menu (three horizontal lines) in the bottom-right corner
3. Tap Settings
4. Go to Data Management under the Privacy section
5. Select Web Site Data and then tap Clear All Web Site Data

1. Open the Settings app on your iPhone
2. Scroll down and tap Safari
3. Scroll down to find and select Clear History and Website Data