А вы можете понять где он тут засовывает то что

он сгенерировал в primaryKey;

<?php

namespace Illuminate\Database\Eloquent\Concerns;

use Illuminate\Database\Eloquent\ModelNotFoundException;
use Illuminate\Support\Str;

trait HasUlids
{
/**
* Initialize the trait.
*
* @return void
*/
public function initializeHasUlids()
{
$this->usesUniqueIds = true;
}

/**
* Get the columns that should receive a unique identifier.
*
* @return array
*/
public function uniqueIds()
{
return [$this->getKeyName()];
}

/**
* Generate a new ULID for the model.
*
* @return string
*/
public function newUniqueId()
{
return strtolower((string) Str::ulid());
}

/**
* Retrieve the model for a bound value.
*
* @param \Illuminate\Database\Eloquent\Model|\Illuminate\Database\Eloquent\Relations\Relation $query
* @param mixed $value
* @param string|null $field
* @return \Illuminate\Database\Eloquent\Relations\Relation
*
* @throws \Illuminate\Database\Eloquent\ModelNotFoundException
*/
public function resolveRouteBindingQuery($query, $value, $field = null)
{
if ($field && in_array($field, $this->uniqueIds()) && ! Str::isUlid($value)) {
throw (new ModelNotFoundException)->setModel(get_class($this), $value);
}

if (! $field && in_array($this->getRouteKeyName(), $this->uniqueIds()) && ! Str::isUlid($value)) {
throw (new ModelNotFoundException)->setModel(get_class($this), $value);
}

return parent::resolveRouteBindingQuery($query, $value, $field);
}

/**
* Get the auto-incrementing key type.
*
* @return string
*/
public function getKeyType()
{
if (in_array($this->getKeyName(), $this->uniqueIds())) {
return 'string';
}

return $this->keyType;
}

/**
* Get the value indicating whether the IDs are incrementing.
*
* @return bool
*/
public function getIncrementing()
{
if (in_array($this->getKeyName(), $this->uniqueIds())) {
return false;
}

return $this->incrementing;
}
}

Описание группы прочитай и такие простыни в чат не кидай