Startx not loading on boot up and forced to shutdown on wake up

Support GNOME
,
1

When I start my computer, I get a blank screen. My brother found that it was stratx not loading and found a workaround by going to a tty and back to the GUI.
And when I wake up my PC from sleep, I only get a flashing screen and the workaround doesn’t work, forcing me to hold the power button.
I think those two issues are related.
How can I fix those problems.

2

we need more informations

3

I have dual monitor setup on a AMD Radeon 5500 XT, one DisplayPort @ 165 Hz and another on HDMI converted to VGA.
And on wake up the blinking patterns is ~2 seconds blank, 1/60 second white screen.

4

UPDATE: The blinking is not caused by sleeping but by the automatic black screen.