Doctrine entitymanger not inserting ID column

I have the following Model:

<?php

namespace App\Domain\Model\Meal;

use App\Domain\Model\HasUuid;
use App\Domain\Model\Timestampable;
use App\Domain\Model\User\Child;
use Doctrine\ORM\Mapping as ORM;
use Ramsey\Uuid\Uuid;

#[ORM\Entity]
#[ORM\Table(name: 'meal_opt_out')]
final class MealOptOut
{
    use HasUuid;
    use Timestampable;

    #[ORM\ManyToOne(targetEntity: MealItemSchedule::class)]
    #[ORM\JoinColumn(name: 'meal_item_schedule_id', referencedColumnName: 'id', nullable: false, onDelete: 'CASCADE')]
    private MealItemSchedule $mealItemSchedule;

    #[ORM\ManyToOne(targetEntity: Child::class)]
    #[ORM\JoinColumn(name: 'child_id', referencedColumnName: 'id', nullable: false, onDelete: 'CASCADE')]
    private Child $child;

    public function __construct(
        MealItemSchedule $mealItemSchedule,
        Child $child
    )
    {
        $this->id = Uuid::uuid4()->toString();
        $this->mealItemSchedule = $mealItemSchedule;
        $this->child = $child;
    }
    
    // Getters and setters...
}

HasUuid trait:

<?php

namespace App\Domain\Model;

use Doctrine\ORM\Mapping as ORM;

trait HasUuid
{
    #[ORM\Id]
    #[ORM\Column(name: 'id', type: 'string', unique: true)]
    protected string $id;

    public function getId(): string
    {
        return $this->id;
    }

    public function setId(string $id): void
    {
        $this->id = $id;
    }
}

I am using a hexagonal architecture, so I have a few interfaces, but the most important file is DoctrineMealOptOutRepository:

<?php

namespace App\Infrastructure\Repository\Meal;

use App\Domain\Model\Meal\MealOptOut;
use App\Domain\Repository\Meal\MealOptOutRepositoryInterface;
use Doctrine\Bundle\DoctrineBundle\Repository\ServiceEntityRepository;
use Doctrine\Persistence\ManagerRegistry;

final class DoctrineMealOptOutRepository extends ServiceEntityRepository implements MealOptOutRepositoryInterface
{
    public function __construct(
        private ManagerRegistry $manager,
    )
    {
        parent::__construct($manager, MealOptOut::class);
    }
    
    /*
    public function save(MealOptOut $mealOptOut): void
    {
        $this->getEntityManager()->persist($mealOptOut);
        $this->getEntityManager()->flush();
    }
     */

    public function save(MealOptOut $mealOptOut): void
    {
        $connection = $this->getEntityManager()->getConnection();
        $sql = '
            INSERT INTO meal_opt_out (id, meal_item_schedule_id, child_id, created_at, updated_at)
            VALUES (:id, :meal_item_schedule_id, :child_id, NOW(), NOW())
        ';
        $params = [
            'id' => $mealOptOut->getId(),
            'meal_item_schedule_id' => $mealOptOut->getMealItemSchedule()->getId(),
            'child_id' => $mealOptOut->getChild()->getId(),
        ];

        $connection->executeStatement($sql, $params);
    }
}

MealOptOutRepositoryInterface:

<?php

namespace App\Domain\Repository\Meal;

use App\Domain\Model\Meal\MealOptOut;

interface MealOptOutRepositoryInterface
{
    public function save(MealOptOut $mealOptOut): void;
}

MealOptOutServiceInterface:

<?php

namespace App\Domain\Service\Meal;

use App\Domain\Model\Meal\MealItemSchedule;
use App\Domain\Model\Meal\MealOptOut;
use App\Domain\Model\User\Child;


interface MealOptOutServiceInterface
{
    public function saveMealOptOut(MealOptOut $mealOptOut): ?MealOptOut;
}

MealOptOutServiceImplementation:

<?php

namespace App\Domain\Service\Meal\Impl;

use App\Domain\Model\Meal\MealItemSchedule;
use App\Domain\Model\Meal\MealOptOut;
use App\Domain\Model\User\Child;
use App\Domain\Repository\Meal\MealOptOutRepositoryInterface;
use App\Domain\Service\Meal\MealOptOutServiceInterface;
use Doctrine\Bundle\DoctrineBundle\Repository\ServiceEntityRepository;
use Doctrine\Persistence\ManagerRegistry;
use Ramsey\Uuid\Uuid;

final class MealOptOutServiceImplementation extends ServiceEntityRepository implements MealOptOutServiceInterface
{
    public function __construct(
        private MealOptOutRepositoryInterface $mealOptOutRepository,
        private ManagerRegistry $manager,
    )
    {
        parent::__construct($manager, MealOptOut::class);
    }

    public function saveMealOptOut(MealOptOut $mealOptOut): ?MealOptOut
    {
        return $this->mealOptOutRepository->save($mealOptOut);
    }
}

The service is called like this:

$mealOptOut = new MealOptOut($this->selectedMealItemSchedule, $child);
// $mealOptOut->setId(Uuid::uuid4()->toString());
$this->mealOptOutService->saveMealOptOut($mealOptOut);

The problem is that when I use this version of save in DoctrineMealOptOutRepository

    public function save(MealOptOut $mealOptOut): void
    {
        $this->getEntityManager()->persist($mealOptOut);
        $this->getEntityManager()->flush();
    }

I get the following error:

An exception occurred while executing a query: SQLSTATE[HY000]: General error: 1364 Field 'id' doesn't have a default value
...

at Doctrine\DBAL\Connection->convertExceptionDuringQuery(object(Exception), 'INSERT INTO meal_opt_out (created_at, updated_at, meal_item_schedule_id, child_id) VALUES (?, ?, ?, ?)', array(null, null, 'f8ab33de-ab9d-11ef-bcf3-44da78cb937b', 'a440ab82-573d-4475-a9e3-b5bf839352ed'), array('datetime', 'datetime', 'string', 'string'))

You see in the log that the entitymanager is for some reason not inserting the id column. I am 100% sure the id is set though. I am using the exact same architecture and trait for other entities, and it works for them. I tried auto-generating the uuid but also that didn't help.

Temporarily I have it fixed by executing the SQL manually (which does work, indicating the ID is indeed correctly set).

What am I doing wrong?

I found the solution. I had a Timestampable trait

<?php

namespace App\Domain\Model;
use DateTime;
use Doctrine\ORM\Mapping as ORM;

trait Timestampable
{
    #[ORM\Column(type: 'datetime', nullable: true)]
    #[ORM\GeneratedValue(strategy: 'AUTO')]
    protected DateTime $createdAt;
    
    #[ORM\Column(type: 'datetime', nullable: true)]
    #[ORM\GeneratedValue(strategy: 'AUTO')]
    protected DateTime $updatedAt;

    public function setCreatedAt(): void
    {
        $this->createdAt = new \DateTime();
    }

    public function getCreatedAt(): DateTime
    {
        return $this->createdAt;
    }

    public function setUpdatedAt(): void
    {
        $this->updatedAt = new \DateTime();
    }

    public function getUpdatedAt(): DateTime
    {
        return $this->updatedAt;
    }

    public function updateTimestamps(): void
    {
        if ($this->createdAt === null) {
            $this->setCreatedAt();
        }
        $this->setUpdatedAt();
    }
}

which caused issues, editing the trait solved the issue:

<?php

namespace App\Domain\Model;

use DateTime;
use Doctrine\ORM\Mapping as ORM;

trait Timestampable
{
    #[ORM\Column(type: 'datetime', nullable: true)]
    protected DateTime $createdAt;
    
    #[ORM\Column(type: 'datetime', nullable: true)]
    protected DateTime $updatedAt;

    #[ORM\PrePersist]
    public function setCreatedAt(): void
    {
        $this->createdAt = new \DateTime();
    }

    public function getCreatedAt(): DateTime
    {
        return $this->createdAt;
    }

    #[ORM\PreUpdate]
    public function setUpdatedAt(): void
    {
        $this->updatedAt = new \DateTime();
    }

    public function getUpdatedAt(): DateTime
    {
        return $this->updatedAt;
    }

    public function updateTimestamps(): void
    {
        if ($this->createdAt === null) {
            $this->setCreatedAt();
        }
        $this->setUpdatedAt();
    }
}