surface 4 dock issue

I have my Surface 4 configured to turn off the screen after 5 minutes. My setup: Surface 4 Pro Surface 4 dock (brick style) Belkin Mini Displayport to HDMI adapter Asus VE247 Monitor - 1920 x 1080, 23.6" When docked, I use only my monitor. Problem: When the screen turns off after 5 minutes...