Help me troubleshoot, OMV server starts up, but I can't get to GUI and no services run

I have an HP server running OMV. I plugged in a VGA on the server and OMV starts up and prompts me to log in. But when I go to a pc and try to get to the GUI, it doesn't work, or when I try to get to any services, sab, emby, sonarr, etc, none of the pages load. Already rebooted 2-3 times. It was working fine last night, then this AM this prob just started.

Does cache build up somewhere? and how can I clean from the terminal?

my /dev/sda1 is 99% full after running df -h . What command cleans some of that up?