To configure NFC tags you need to use an Android device. First download the Allhours app for Android: https://play.google.com/store/apps/details?id=si.spica.allhours&hl=en.
Then log in and simply touch the NFC tag while the app is open and you will be presented with the clock-in options and choose an event - please do not remove the NFC chip until the process is finished. Once the clock-in has been accepted, you will be prompted that the event has been recorded on an unknown NFC tag.
Then log in to the web app, go to the 'Add NFC tag' and confirm the new unknown tag: