Hello,
If the devices have an internet connection and their RMS Service is enabled (This can be checked in the Services -> Management page), the devices should connect automatically, though it may take several minutes. If the devices are still not connecting, I would suggest, if possible, to go to at least one of the device's WebUI RMS page and check if there is any error displayed.
If you encounter such an error please send me a private message with your RMS company name and the mentioned error, and I will look further into this issue.