Blipbr devices are focussed on preserving as much battery life as possible, so they communicate only when a movement trip is detected.
For the rest of the time, your Blipbr will rest in deep sleep mode, conserving as much battery lifes as possible, with only it's accelerometer awake in order to detect any potential movement.
An exception to this is when your Blipbr is in Recovery Mode.
So, the offline status is perfectly normal, it means your Blipbr is enjoying some well deserved rest, and more importantly, your valuable stuff isn't moving anywhere!