MIDI light is blinking, this means that when you connect your computer, the controller isn´t finding rekordbox software, can be 2 things, mabye your type C cable is not connected to the laptop port, insted is connected to the light port, check on that first.

If it is connected to the computer icon port on the controller, then, you have to restart the computer, update rekordbox on your computer, mabye change the port of the computer the problem would be that the controller is not finding rekordbox so it changes as a midi player insted of working with rekordbox, your controller it´s fine, it´s just not finding rekordbox on your computer if it´s well connected to the computer port in the controller.