All of my Zigbee unit is just suddenly not responding

All of a sudden all (about 7) Zigbee devices are disconnected from the network. They all have a spinning wheel indicating that they are not connected. When I try to reconnect to Zigbee, I just get “driver_not_ready”. I have disconnected the Homey HUB and also restored it. But the problem is still the same. All the devices have been working for years. Any tips?

Which Homey model?
Ball: replace power brick, if not sufficient, restart in recovery mode and install “Full software download” - This installs the firmware from scratch.
Puck: Connect to a pc / laptop and choose “install firmware”.