How to make a one-to-one connection?

Question

Laravel

Hello, tell me please, I have two models:

1. Category
   
2. Image
   

I would like to make a one-to-one relationship between Category and Image, because a category can only have one image
. In the categories migration, there is this:

$table->unsignedBigInteger('image_id')->nullable();
$table->foreign('image_id')->references('id')->on('images'); //id картинки

This is the Category model

class Category extends Model
{
    public function image() //Вернёт картинку категории
    {
        return $this->hasOne('App\Models\Admin\Image');
    }
}

This is the Image model

class Image extends Model
{
    public function category() //Получить категорию
    {
        return $this->belongsTo('App\Models\Admin\Category');
    }
}

But in fact, the image method from Category does not return a category image, no matter what I try, tell me please what can be changed here?