This message relate to the maximum number of streamings in progress at a given time. Keep in mind that, although you can use HBO GO on several devices, you can only watch videos on two devices at the same time. Verify if a video is streaming on other devices, if so, stop it and completely shutdown the video stream. Please wait 90 minutes and try again. We also suggest that you update your active devices in your device management list and try again in 12 hours.