Model SpentTime

No puedo guardar los datos de cálculo por categoría cuando creo nuevos datos en laravel

public static function findOrCreate($plan_id, $data)
{
    $fromDate = Carbon::now()->subDay()->startOfWeek()->toDateString();
    $nowDate = Carbon::now()->today()->toDateString();

    $spent_time = static::where('plan_id', $plan_id)->first();

    if (is_null($spent_time)) {
        return static::create($data);
    }else{
        $task_category = SpentTime::where('task_category', $spent_time->task_category)->get();
        $create_spent_times = SpentTime::where('task_category', $spent_time->task_category)->sum('daily_spent_time', $fromDate);
        $request['spent_time'] = (int)$create_spent_times + $spent_time->daily_spent_time;

        $create_spent_times = SpentTime::where('task_category', $spent_time->task_category)->sum('daily_percentage', $fromDate);
        $request['percentage'] = (int)$create_spent_times + $spent_time->daily_percentage;

        $spent_time->save();
        return $spent_time->update($data);
    }
}

TrackerController

Esta es la función del controlador para almacenar datos:

public function store(Request $request)
{      
    $spent_time = SpentTime::findOrCreate($request->get('plan_id'), [
        'plan_id' => $request->get ('plan_id'),
        'daily_spent_time' => $request->get ('daily_spent_time'),
        'daily_percentage' => $request->get ('daily_percentage'),
        'reason' => $request->get ('reason')
    ]);
    return redirect()->route('real.index', compact( 'spent_time'));
}