In this case you are probably using your ZARPAX in a bathroom or similar space with fluctuating humidity levels. You can do this, but the strong fluctuations in the humidity level confuse the indicator. When the indicator keeps turning back to blue shortly after taking a bath or shower, the ventilation in the room itself is probably enough to take care of any excess moisture in the air. When ZARPAX is full of moisture, the product will no longer be able to remove any more moisture from the air. The indicator will change color depending on the current humidity level in the room. All you need to do is to regenerate it to restore its dehumidifying function.