External monitor turning dark after seconds.

Hi, im trying to use a external hdmi monitor with my m1 macbook air. I have bought a Verbatim usb-c multiport adapter with hdmi. When i connect any display with the hdmi connector the display works perfectly for 10 seconds and then only displays a black image. It's still recognized by macos and is not shut down. when i change the refreshrate in macos the monitor works again for 10 seconds and goes black again. I have tried different monitors and different hdmi cables. I tried the multiport usbc adapter on my asus laptop and it works as intendet with no problem. I have also tried the DisplayLink macOS Software with no success.

Any idea whats the problem here?