This issue is recognized by not seeing any consumption in the Eliq app or web. Another thing to look at is the lamps on the front of the hub, all of which probably will not be lit.
The first thing to do in this case is to restart the hub and check if all lamps are lit during startup. If not, the hub is probably dead and cannot be fixed.
If all lamps are lit during startup, but the hub still doesn't connect, try to replace the power adapter. The power adapter might have gone bad which means it cannot provide the hub with the power it needs to function.
To summarize: Try a different power adapter.