❔ Delegate never assigned to (SOLVED!)

public class BombermanPlayerChannel : ScriptableObject {
    public delegate void BombermanPlayerMovementAction(InputAction.CallbackContext context);
  private BombermanPlayerMovementAction OnBombermanPlayerMovementRequested0; // <--- warning on this line saying "Is never assigned to"
    private BombermanPlayerMovementAction OnBombermanPlayerMovementRequested1;

    private BombermanPlayerMovementAction GetMovementActionForPlayer(int player_index) {
        switch (player_index) {
            case 0:
                return OnBombermanPlayerMovementRequested0;
            case 1:
                return OnBombermanPlayerMovementRequested1;
        }
        throw new System.Exception("Unexpected player index!");
    }

  public void RegisterForMovementAction(int player_index, BombermanPlayerMovementAction callback) {
        GetMovementActionForPlayer(player_index) += callback;
        
        // Also tried this:
    BombermanPlayerMovementAction action = GetMovementActionForPlayer(player_index);
    action -= callback;
    }

  public void RaiseMovementEvent(int player_index, InputAction.CallbackContext context) {
    BombermanPlayerMovementAction action = GetMovementActionForPlayer(player_index);
    if (action != null) {
      action.Invoke(context);
    }
  }