Display goes to sleep and I can't wake it up

Hello everyone,

My Samsung P2770FH Display switches to energy saving mode everytime I use it after like 30 minutes (for no reason, I’m constantly using the PC). The power LED is blinking but I can’t get the monitor to wake up, neither by pressing buttons on the computer nor by pressing the power button on the display.

The computer has KDE Neon 5.18 installed.

Thanks for your help