Let's try to fix things by resetting the Hub.
Use a pen tip to press and hold the reset button on the back of the Hub for 10 seconds. Now leave the Hub for 10 minutes to reset.
When the white power light’s solidly lit, check if you’re back online
Running a reset will wipe any changes you’ve made to the Hub’s settings. This could include changes to the WiFi password or network name.
This could take up to 30 seconds