I have been using the USB C Triple Display Docking station connecting and charging my HP Spectre i7 15" for the last month and it has been working great.
Now all of a sudden it keeps flickering the power on and off and will not stay on . It keeps flickering the power on and off.
That docking station is rated to push 60W of power, but the power brick for the HP Spectre x360 15" 2017 (i7 model) I have is labelled 90W.
I expect this would charge your laptop slowly during regular use, but drain the battery during heavy use. Perchance, does the power flickering occur when your battery is drained?