Monitor detected but with no signal in Linux Mint and Ubuntu

I have a Slimbook laptop with an external monitor (HP Elitedisplay E243) connected to it using HDMI. Suddenly, the monitor stopped working (it was at a system start). The monitor gets detected by the Linux Mint desktop (21.04 Cinnamon), but no signal is shown. It even seems to wake up when I unplug/plug the HDMI cable, but shows no image. This is the output of the xrandr command:

Screen 0: minimum 320 x 200, current 1920 x 1080, maximum 16384 x 16384eDP-1 connected primary 1920x1080+0+0 (normal left inverted right x axis y axis) 309mm x 173mm   1920x1080     60.01*+  60.01    59.97    59.96    59.93    40.00     1680x1050     59.95    59.88     1600x1024     60.17     1400x1050     59.98     1600x900      59.99    59.94    59.95    59.82     1280x1024     60.02     1440x900      59.89     1400x900      59.96    59.88     1280x960      60.00     1440x810      60.00    59.97     1368x768      59.88    59.85     1360x768      59.80    59.96     1280x800      59.99    59.97    59.81    59.91     1152x864      60.00     1280x720      60.00    59.99    59.86    59.74     1024x768      60.04    60.00     960x720       60.00     928x696       60.05     896x672       60.01     1024x576      59.95    59.96    59.90    59.82     960x600       59.93    60.00     960x540       59.96    59.99    59.63    59.82     800x600       60.00    60.32    56.25     840x525       60.01    59.88     864x486       59.92    59.57     800x512       60.17     700x525       59.98     800x450       59.95    59.82     640x512       60.02     720x450       59.89     700x450       59.96    59.88     640x480       60.00    59.94     720x405       59.51    58.99     684x384       59.88    59.85     680x384       59.80    59.96     640x400       59.88    59.98     576x432       60.06     640x360       59.86    59.83    59.84    59.32     512x384       60.00     512x288       60.00    59.92     480x270       59.63    59.82     400x300       60.32    56.34     432x243       59.92    59.57     320x240       60.05     360x202       59.51    59.13     320x180       59.84    59.32  DP-1 disconnected (normal left inverted right x axis y axis)HDMI-1 disconnected (normal left inverted right x axis y axis)HDMI-2 connected 1920x1080+0+0 (normal left inverted right x axis y axis) 527mm x 296mm   1920x1080     60.00*+  50.00    59.94     1680x1050     59.88     1600x900      60.00     1280x1024     60.02     1440x900      59.90     1280x800      59.91     1280x720      60.00    50.00    59.94     1024x768      60.00     800x600       60.32     720x576       50.00     720x480       60.00    59.94     640x480       60.00    59.94     720x400       70.08  

What I find a bit strange, is that the monitor seems to be detected at HDMI-2 port, but the laptop only has one DisplayPort port, one HDMI port and a usb-c port. The monitor itself works when other computer gets connected, with same cable.

Tried also with the Ubuntu 22.04 live CD and same result...

What could be going on?