Firstly, ensure that the detector is properly powered with either 12 or 24 volts DC as specified. Check the wiring connections to make sure they are secure and properly terminated. It’s crucial to verify that the detector is compatible with your fire alarm control panel. If everything seems fine electrically, then it’s time to assess the detector itself. Clean the detector chamber thoroughly as accumulated dust or debris can interfere with its sensing capabilities. If the issue persists, consider testing the detector in a controlled environment with approved testing equipment to verify its functionality accurately. If all else fails, it might be necessary to replace the detector unit.