Controller charging but LED not blinking

Bought a 2nd hand DS3 controller, and got a third-party charging cable. I disassembled my PS3 controller to check the motherboard, and its genuine, no doubt.

Connected to PC via SCPToolkit (and bluetooth).

Problem: When the controller is plugged in, its charging, and there is 1 LED, but its not blinking. After a 30 minutes connection, as seen in SCP Monitor, the charge level increased from “Medium” to “High”.

Is my controller or cable defective?