php - Symfony validation wrong type invalid value

one text

I have an entity with the following property and Type validation but i always get a wrong type error validation.wrong_type, when i debug it says invalid value it seems that the Space isnt denormalized maybe?

/**
 * @var Space|null
 * @Assert\Valid(groups={"Default"})
 * @Assert\Type(Space::class, message=Message::VALIDATION_MESSAGE_WRONG_TYPE, groups={"Default"})
 */
public $space;

This is what my Space entity looks like:

final class Space
{
    /**
     * @var float|null
     * @Assert\NotBlank(message=Message::VALIDATION_MESSAGE_NOT_BLANK, groups={"Default","Partial"})
     * @Assert\Type(type="float", message=Message::VALIDATION_MESSAGE_WRONG_TYPE, groups={"Default","Partial"})
     */
    public $value;

    /**
     * @var string|null
     * @Assert\NotBlank(message=Message::VALIDATION_MESSAGE_NOT_BLANK, groups={"Default","Partial"})
     * @Assert\Type(type="string", message=Message::VALIDATION_MESSAGE_WRONG_TYPE, groups={"Default","Partial"})
     */
    public $unit;
}

This is how I pass it in my request:

"space": {
  "value": 54.47,
  "unit": "m??"
},

What am I doing wrong here