USB-C is a connector shape, not a capability. Two identical-looking ports can differ wildly in what they carry, which is why a cable that charges your laptop may refuse to drive a monitor.

Three separate things to check

• Power delivery. Quoted in watts. A port that tops out well below your laptop's requirement will charge slowly or only while asleep.
• Data rate. Ranges from USB 2.0 speeds to far faster standards on the same connector. Bulk file transfer is where the difference is felt.
• Display output. Requires DisplayPort Alt Mode. Without it the port will never output video, whatever adapter you attach.

Cables matter more than people expect

A cable can bottleneck all three. Charge-only cables carry no useful data, and a cable rated for lower power will limit a capable dock. When something behaves oddly, swap the cable before replacing the dock.