So you got your MAG setup for your subscription, and you get this error while loading, the possible reason for this issue is that your MAG is not detecting internet connection.
Page loading error.
Check this section towards the right.
Make sure you are connected to a router and not a modem, a combo unit, preferably.
Causes are either direct or indirect as through a wifi or modem/router.
Modem is not in service or offline
Router is not getting internet from modem
Internet port damaged or wifi antenna device is bad
Lose connection or broken/damaged wires
Software configuration is not properly set
So the possible culprit maybe internet connectivity, so make sure you are properly connected either by wifi or manually connected.
Reconnect through direct manual connection
Look at ethernet, if not connected/enabled then, check/connect the cables on the back, make sure the cable works well, try both ends and assure that modem and router are linked to each other in the ports. Try a different port in the back of the router, make sure the router works , you can also turn off and turn on the router to clear and reset connection. So make sure you get it enabled, make sure both the router and modem are connected and are receiving data as online, your ip address should be visible and your ethernet now appearing enabled.
Reconnect to the wifi internet in configuration.
Click System Settings, Network, Wireless or Wifi, Select auto DHTP, Select the wireless connection you want to use,
Verify the SSID,is the one you want to us, in Authentication mode select your choice or default., Select Encryption as default or open or configure to encrypt as or TKIP, if not open enter the password and save. Once configured you should be able to connect properly.
If nothing works continue troubleshooting router/modem until all is enabled, a definitive resource can be a factory reset which will help recover your device to a fresh state.
Now this can be one of many scenarios to the cause of not connecting with your MAG device, keep troubleshooting and continue trying different options until you find your resolution.