I have a Desktop PC running Ubuntu 20.04. I mainly connect to this computer using TeamViewer (it's in the office and I'm working from home like so many of us). The computer's been working fine for about a year now. However, this morning when I connected to it the screen was frozen. I did a reboot and after that all I get is a black screen. I can still connect with TeamViewer but I just get a black screen and it doesn't respond to any mouse or keyboard input. I can connect and interact with it through SSH so obviously it's still online, it seems it's just the GUI (gnome) that's not working.
Grateful for any advice here.