controller

 // ------------------------------Prepaid card info Text Box---------------------------------------

        public function prepaid_card()
    {
        $data['title'] = "Prepaid card info";
        $setting = $this->setting_model->read();
        $data['prepaid_card']=$setting->prepaid_card;

        // print_r($data);die();

        $data['content'] = $this->load->view('backend/dashboard/company_instruction',$data,true);
        $this->load->view('backend/layout/main_wrapper',$data);
    }



    public function prepaid_card_update()
    {
        if($this->input->post()){
            $data['setting_id']=1;
            $data['company_instruction']= $this->input->post('prepaid_card');

            //print_r($data);die();
        
            $this->setting_model->update($data);
            $this->session->set_flashdata('message',display('update_successfully'));
            redirect('backend/dashboard/setting/prepaid_card');
        }
    }

model

 

       public function read()
    {
        return $this->db->select("*")
            ->from($this->table)
            ->get()
            ->row();
    }
    
      public function update($data = [])
    {
        return $this->db->where('setting_id',$data['setting_id'])
            ->update($this->table,$data);
    } 

 view page

  <script src="https://cdn.ckeditor.com/4.11.4/standard-all/ckeditor.js"></script>
    <div class="app-content content">
        <div class="content-wrapper">


            <div class="row match-height">
                

                <!-- my task Timeline -->
                <div class="col-xl-12 col-lg-12">
                    <div class="card">
                        <div class="card-header border-0">
                            <h4 class="card-title"><?php echo (!empty($title)?$title:null) ?></h4>
                            <div class="heading-elements">
                                <ul class="list-inline">
                                    <li><a data-action="reload"><i class="feather icon-rotate-cw"></i></a></li>
                                    <li><a data-action="expand"><i class="feather icon-maximize"></i></a></li>
                                </ul>
                            </div>
                        </div>

                        <div class="card-content">
                            <div class="card-body">

                   <?php echo form_open_multipart("backend/dashboard/setting/prepaid_card_update") ?>

                   
                    <div class="form-group row">
                        <label for="article1_en" class="col-sm-2 col-form-label">Prepaid card info<i class="text-danger">*</i></label>
                        <div class="col-sm-10">
                            
                            <textarea cols="80" id="editor3" name="prepaid_card" rows="10" placeholder="Popup Content>" data-sample-short><?php echo $prepaid_card ?></textarea>

                                                <div class="row">
                        <div class="col-sm-9 col-sm-offset-2 mt-4">
                            <a href="<?php echo base_url('admin'); ?>" class="btn btn-primary  w-md m-b-5"><?php echo display("cancel") ?></a>
                            <button type="submit" class="btn btn-success  w-md m-b-5"><?php echo display("update") ?></button>
                        </div>
                    </div>
                        </div>
                    </div>
                   

             <?php echo form_close();?>


                            </div>
                        </div>
                    </div>
                </div>
            </div>


        </div>
    </div>
<script>
    // We need to turn off the automatic editor creation first.
    CKEDITOR.disableAutoInline = true;

    CKEDITOR.replace('editor3', {
      extraPlugins: 'sourcedialog',
      removePlugins: 'sourcearea'
    });
  </script>