MacBook Pro 14 M1 Pro treating Dell WD19TB only as power source

Hello,

I got a Dell WD19TB in order to use it with my Gigabyte M27Q screen. I connected the screen to the dock using a thunderbolt cable and connected a mouse and keyboard to it. I am using an external power source adapter with 180W.

However, even without the screen, the dock is not recognized by the macbook. It only treats it as a power source and charges the macbook but doesn't detect the mouse and the keyboard at all.

If I go to system information, I don't see any thunderbolt port having a device connected to it.

Do I have a defective unit or am I doing something wrong? Any help is appreciated!