PS4 Controller won't start

Hi, i have a qestion and hope you guys have an idea.

I changed the usb-charging-port and the battery of my ps4-Controller, but the Controller won’t start.
Not even when i connect it to the running PS4 via USB-Cable. It dont brings up the “blue-light” what my other controllers do when starting/connecting. When i press the PS-Button nothing seems to happen.

Do you guys have any idea what the problem could be?

I have the exact same problem, but cannot seem to find the solution anywhere.

Any solution to this problem?