I figured that was the problem. A simple reboot might reconnect the hub. If that doesn't fix it, go to Settings and select Hub Details, then click on Update from Browser (that would syncronize the hub's internal clock) as @aaiyar suggested. If all fail, then I would look at your network and firewall settings to make sure the hub is allowed to connect to the internet. Hub connected to a subnet is common reason why the hub might not be able to reach the cloud.
Download the Hubitat app
