Problem zigbee rgbw light, white always on


Ive got a Paulmann 500.47 Zigbee rgbw led controller.
My problem is, I cant turn the white leds off.

Its recognized by zigbee, I can change the colors with the palette wheel, but it wouldn’t turn the white leds off.

Ive red something of changing the light entity supported_color_ modes to rgbw, but I dont know how or where. The controller is configured as rgb, xy and hs color.

Thanks for your help!