Models insert() and save() methods return "unknown error" but the query builder works

I'm trying to get user creation functionality working on a signup page. When the form is submitted I use either

Code:

$user->insert($data)

or

Code:

$user->save($data)

. When I call

Code:

$user->error()

it returns "Unknown error" with a code of "101".

If I try to insert the same date using the Query Builder then it works correctly.

Am I using the model class incorrectly?

Here is my code for the method:

PHP Code:

public function create()
 {
        $user = new User();

        $rules = [
            'username' => 'required|min_length[2]|alpha_numeric',
            'email' => 'required|valid_email',
            'password' => 'required',
            'password_confirm' => 'required|matches[password]'
        ];

        /**------------------------------------------------------------------------------
        * Validation
        ------------------------------------------------------------------------------*/
        if (! $this->validate($user->validationRules))
        {
            echo view('login/signup', [
                'validation' => $this->validation,
            ]);
        } else
        {
            $username = $this->request->getVar('username');
            $email = $this->request->getVar('email');
            $password = $this->request->getVar('password');

            $userFound = $user->where('username', $username)->first();
            $emailFound = $user->where('email', $email)->first();

            $data = [
                'username' => $username,
                'email' => $email,
                'password' => password_hash($password, PASSWORD_DEFAULT)
            ];

            dump($user->insert($data));
            dump($user->error());

            $this->session->setFlashdata("message", "An account for <strong>{$username}</strong> has been created. Now you can login!");
            return redirect()->to('/login');
        } 


look my codes 

PHP Code:

<?php
namespace CoreCommon\Controllers;


use CoreCommon\Entities\AdvertisementMediaEntity;

use CoreCommon\Libraries\CustomFileSystem;
use CoreCommon\Models\AdvertisementMediaModel;
use CodeIgniter\HTTP\ResponseInterface;


class AdvertisementMedia extends ApiController
{


    /**
    * index function
    * @method : GET
    */
    public function index()
    {

        $advertisementMediaModel = new AdvertisementMediaModel();

        $result = $advertisementMediaModel->select($this->urlQueryParam->getFiled())
            ->whereIn($this->urlQueryParam->extractQueryKey('in'), $this->urlQueryParam->extractQueryValue('in'))
            ->whereNotIn($this->urlQueryParam->extractQueryKey('nin'), $this->urlQueryParam->extractQueryValue('nin'))
            ->orWhereIn($this->urlQueryParam->extractQueryKey('oin'), $this->urlQueryParam->extractQueryValue('oin'))
            ->orWhereNotIn($this->urlQueryParam->extractQueryKey('onin'), $this->urlQueryParam->extractQueryValue('onin'))
            ->where($this->urlQueryParam->extractQueryArray('whr'))
            ->orWhere($this->urlQueryParam->extractQueryArray('owr'))
            ->like($this->urlQueryParam->extractQueryArray('lik'))
            ->orLike($this->urlQueryParam->extractQueryArray('olk'))
            ->orderBy($this->urlQueryParam->getSort(), $this->urlQueryParam->getOrder())
            ->paginate($this->urlQueryParam->getLimit(), 'default', $this->urlQueryParam->getPage(), $this->urlQueryParam->getOffset());



        return $this->respond([
            'data' => $result,
            'pager' => $advertisementMediaModel->pager->getDetails()
        ], ResponseInterface::HTTP_OK, lang('Common.api.receive'));

    }

    /**
    * show function
    * @method : GET with params ID
    */
    public function show($id = null)
    {
        $advertisementMediaModel = new AdvertisementMediaModel();


        return $this->respond([

            'data' => $advertisementMediaModel->where('id', $id)->paginate(1, 'default'),
            'pager' => $advertisementMediaModel->pager->getDetails()
        ], ResponseInterface::HTTP_OK,  lang('Common.api.receive'));


    }

    /**
    * create function
    * @method : POST
    */
    public function create()

    {


        $advertisementMediaModel = new AdvertisementMediaModel();
        $customConfig = new \CoreCommon\Config\CoreCommonConfig();
        $imageService =    \CodeIgniter\Config\Services::image();
        $advertisementMediaEntity = new AdvertisementMediaEntity();


        if ($this->request->getPost()) {

            $rules = [
                'image' => 'uploaded[image]|max_size[image,4096]|ext_in[image,png,jpg,mp4,gif,webp]',

            ];
            if (!$this->validate($rules)) {

                return $this->respond([
                    'error' => $this->validator->getErrors(),
                    'success' => false
                ], ResponseInterface::HTTP_NOT_ACCEPTABLE, lang('Common.api.validation'));

            }

            $advertisementMediaEntity->advertisement_id = $this->request->getPost('advertisement_id');

            if (isset($_FILES['image'])) {

                foreach ($this->request->getFileMultiple('image') as $avatar) {


                    $avatar->move($customConfig->uploadDirectory . '/advertisement', time() . '.' . $avatar->getClientExtension());


                    $advertisementMediaEntity->path = $avatar->getName();
                    $advertisementMediaEntity->editPath($avatar->getExtension() != 'mp4');

                    if (!$advertisementMediaModel->save($advertisementMediaEntity)) {

                        return $this->respond([
                            'error' => $advertisementMediaModel->errors(),
                            'success' => false,
                        ], ResponseInterface::HTTP_BAD_REQUEST,  lang('Common.api.reject'));

                    }
                }


            }


            return $this->respond([
                'data' => ''
            ], ResponseInterface::HTTP_CREATED, lang('Common.api.save'));

        }

    }

    /**
    * update function
    * @method : PUT or PATCH
    */
    public function update($id = null)
    {


        $advertisementMediaModel = new AdvertisementMediaModel();
        $customConfig = new \CoreCommon\Config\CoreCommonConfig();
        $imageService =    \CodeIgniter\Config\Services::image();
        $handy = new CustomFileSystem();
        $advertisementMediaEntity = new AdvertisementMediaEntity();
        $adsMedia = null;

        if ($this->request->getPost()) {

            $rules = [
                'image' => 'uploaded[image]|max_size[image,4096]|ext_in[image,png,webp,jpeg,jpg,mp4,gif]',

            ];

            if (!$this->validate($rules)) {

                return $this->respond([
                    'error' => $this->validator->getErrors(),
                    'success' => false,
                ], ResponseInterface::HTTP_NOT_ACCEPTABLE, lang('Common.api.validation') );

            }


            $adsMedia = $advertisementMediaModel->where('id', $id)->first();

            if (is_null($adsMedia)) {
                return $this->respond([
                    'error' => $this->validator->getErrors(),
                    'success' => false
                ], ResponseInterface::HTTP_NOT_FOUND, lang('Common.api.exist'));
            }

            $advertisementMediaEntity->id = $id;
            $advertisementMediaEntity->advertisement_id = $adsMedia->advertisement_id;
            if (isset($_FILES['image'])) {

                foreach ($this->request->getFileMultiple('image') as $avatar) {

                    if ($avatar->getExtension() == 'mp4')
                        $avatar->move($customConfig->uploadDirectory . '/advertisement/video', time() . '.' . $avatar->getClientExtension());
                    else
                        $avatar->move($customConfig->uploadDirectory . '/advertisement/image', time() . '.' . $avatar->getClientExtension());

                    $advertisementMediaEntity->path = $avatar->getName();

                    $advertisementMediaEntity->editPath($avatar->getExtension() != 'mp4');

                    if (!$advertisementMediaModel->update($id, $advertisementMediaEntity)) {

                        return $this->respond([
                            'error' => $advertisementMediaModel->errors(),
                            'success' => false,

                        ], ResponseInterface::HTTP_BAD_REQUEST,  lang('Common.api.reject'));

                    }
                }


            }


            $handy->removeSingleFile(ROOTPATH . $adsMedia->path);

            return $this->respond([
                'data' => array(['id' => $id,
                    'advertisement_id' => $adsMedia->advertisement_id,
                    'path' => $advertisementMediaEntity->path])
            ], ResponseInterface::HTTP_OK,  lang('Common.api.update'));
        }

    }

    /**
    * edit function
    * @method : DELETE with params ID
    */
    public function delete($id = null)
    {


        $advertisementMediaModel = new AdvertisementMediaModel();
        $handy = new CustomFileSystem();
        $id = ($id == 0 ? 0 : $id);

        if ($id == 0) {

            $isExist = $advertisementMediaModel->where(['advertisement_id' => $this->urlQueryParam->getForeignKey()])->
            findAll();
            $target = array('advertisement_id' => $this->urlQueryParam->getForeignKey());
        } else {
            $isExist = $advertisementMediaModel->where(['id' => $id])->findAll();
            $target = array('id' => $id);
        }


        if ($isExist) {
            $advertisementMediaModel->where($target)->delete();
            foreach ($isExist as $path) {

                $handy->removeSingleFile(ROOTPATH . $path->path);
            }


        }

        return $this->respond([

        ], ResponseInterface::HTTP_OK, lang('Common.api.remove'));

    }

} 


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