If your NFC device cannot contact the transponder it may be due to one of the following reasons:
The NFC device is not close enough to the transponder or is being held at an incorrect angle – reposition the NFC device next to the transponder. On the RT6 App tap: Advanced > NFC Optimise Tool to determine the best position for the NFC device.
The NFC device is not working correctly or has locked – Check/restart the NFC device.
The RT6 App has locked – redstart the RT6 App.
NFC interface has locked – power cycle the RT 6-1000 by removing the battery and waiting 60 seconds before replacing it.