Why the hub does not recover internet connection

1. From periodic booting 

2. Isp break outside of home network?

All other devices including P115 plugs does. We had an hour service break one night 2am and the sensors and hub (+ camera) were still offline in the morning. Sensor data during the rest of night was shown locally during the break but when recovered, it was lost. Same had happened many times.

Where is the (two years) data stored?

The problems is that when the internet is down, you can still see the data but when back online, it disappears!