HDMI is not working but user leds are flashing

hi!
Yesterday I was upgrading the software and installing dependencies, but due to an emergency I left right after the ($ sudo apt-get upgrade -y ) command and have to turn off the board, and when I try to continue the monitor is not displaying anything but the user led in the dragonboard is flashing.
I was hoping someone can help:pray:

thanks.

Which release [1] of Debian are you running, If you’re running < 19.01 than it could be related to this issue:

[1] Linaro Releases