Make sure the dot has been activated beforehand.
iPhone 7, iPhone 8, iPhone X and older must use the NFC scanner in the control center.
Your phone must be updated to iOS 14.
dot cards can not be scanned while:
the flashlight is ON
the phone screen is OFF
their phone is in Airplane Mode
the camera is Open
*Note that the tap feature will not work while the camera is open. As an alternative, scan the custom QR code available on your dot.Profile by using your camera app. A link should pop up which will take you to the dot.Profile.