Error setelah menambahkan content yaitu " Array to string conversion"

Capture.PNGBerikut gambaran diatas form konten yang menyebabkan error ketika memakai tombol add+

Dan dibawah adalah gambar errornya

Capture1.PNG

Berikut codingannya :

Model

<?php

class Report_model extends CI_Model
{

    private $_table = 'report';

    public function get()
    {
        $query = $this->db->get($this->_table);
        return $query->result();
    }

    public function get_published($limit = null, $offset = null)
    {
        if (!$limit && $offset) {
            $query = $this->db
                ->get_where($this->_table, ['draft' => 'FALSE']);
        } else {
            $query =  $this->db
                ->get_where($this->_table, ['draft' => 'FALSE'], $limit, $offset);
        }
        return $query->result();
    }

    public function find_by_slug($slug)
    {
        if (!$slug) {
            return;
        }
        $query = $this->db->get_where($this->_table, ['slug' => $slug]);
        return $query->row();
    }

    public function find($id)
    {
        if (!$id) {
            return;
        }

        $query = $this->db->get_where($this->_table, array('id' => $id));
        return $query->row();
    }

    public function insert($report)
    {
        return $this->db->insert($this->_table, $report);
    }

    public function update($report)
    {
        if (!isset($report['id'])) {
            return;
        }

        return $this->db->update($this->_table, $report, ['id' => $report['id']]);
    }

    public function delete($id)
    {
        if (!$id) {
            return;
        }

        return $this->db->delete($this->_table, ['id' => $id]);
    }
    public function count(){
        return $this->db->count_all($this->_table);
    }
}

Controller

<?php

class Post extends CI_Controller
{
    public function __construct()
    {
        parent::__construct();
        $this->load->model('report_model');
    }
    public function index()
    {
        $data['reports'] = $this->report_model->get();
        if(count($data['reports']) <= 0){
            $this->load->view('admin/post_empty.php');
        } else {
            $this->load->view('admin/post_list.php', $data);
        }
    }
    public function new()
    {
        if ($this->input->method() === 'post') {
            // TODO: Lakukan validasi sebelum menyimpan ke model

            // generate unique id and slug
            $id = uniqid('', true);
            $slug = url_title($this->input->post('title'), 'dash', TRUE) . '-' . $id;

            $report = [
                'id' => $id,
                'title' => $this->input->post('title'),
                'slug' => $slug,
                'content' => $this->input->post('content'),
                'draft' => $this->input->post('draft')
            ];

            $saved = $this->report_model->insert($report);

            if ($saved) {
                $this->session->set_flashdata('message', 'Report was created');
                return redirect('admin/post');
            }
        }

        $this->load->view('admin/post_new_form.php');
    }

    public function edit($id = null)
    {
        $data['report'] = $this->report_model->find($id);

        if (!$data['report'] || !$id) {
            show_404();
        }

        if ($this->input->method() === 'post') {
            // TODO: lakukan validasi data seblum simpan ke model
            $report = [
                'id' => $id,
                'title' => $this->input->post('title'),
                'content' => $this->input->post('content'),
                'draft' => $this->input->post('draft')
            ];
            $updated = $this->report_model->update($report);
            if ($updated) {
                $this->session->set_flashdata('message', 'Report was updated');
                redirect('admin/post');
            }
        }

        $this->load->view('admin/post_edit_form.php', $data);
    }

    public function delete($id = null)
    {
        if (!$id) {
            show_404();
        }

        $deleted = $this->report_model->delete($id);
        if ($deleted) {
            $this->session->set_flashdata('message', 'Report was deleted');
            redirect('admin/post');
        }
    }
}

View

<!DOCTYPE html>
<html lang="en">
    <script src="http://ajax.googleapis.com/ajax/libs/jquery/1.9.1/jquery.js"></script>
    <link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.6/css/bootstrap.min.css">
<head>
    <?php $this->load->view('admin/_partials/head.php') ?>
</head>

<body>
    <main class="main">
        <?php $this->load->view('admin/_partials/side_nav.php') ?>

        <div class="content">
            <h1>Write new Report</h1>

            <form action="" method="POST">
                <label for="title">Title*</label>
                <input type="text" name="title" placeholder="Judul Report" required title="Wajib tulis judul Report"/>
                <div class="control-group after-add-more">
                    <label for="content">Konten</label>
                    <textarea name="content[]" cols="30" rows="10" placeholder="Tuliskan isi pikiranmu..."></textarea>
                </div>
                <br>
                <button class="btn btn-success add-more" type="button">
                    <i class="glyphicon glyphicon-plus"></i> Add
                </button>
                <hr>
                <div>
                    <button type="submit" name="draft" class="button" value="true">Save to Draft</button>
                    <button type="submit" name="draft" class="button button-primary" value="false">Publish</button>
                </div>
            </form>
            <div class="copy hide">
                <div class="control-group">
                    <label for="content">Konten</label>
                    <textarea name="content[]" cols="30" rows="10" placeholder="Tuliskan isi pikiranmu..."></textarea>
                    <br>
                    <button class="btn btn-danger remove" type="button"><i class="glyphicon glyphicon-remove"></i> Remove</button>
                    <hr>
            <?php $this->load->view('admin/_partials/footer.php') ?>
        </div>
    </main>
<script type="text/javascript">
    $(document).ready(function() {
      $(".add-more").click(function(){
          var html = $(".copy").html();
          $(".after-add-more").after(html);
      });

      // saat tombol remove dklik control group akan dihapus
      $("body").on("click",".remove",function(){
          $(this).parents(".control-group").remove();
      });
    });
</script>
</body>

</html>