How to insert form in DataBase I created my form but inserting the base does not work also radios type does not appear in the form

&lt;?php

/**
 * @file
 * Contains \Drupal\contact_form\Form\ContributeForm.
 */

namespace Drupal\contact_form\Form;
use Drupal\Core\DependencyInjection\ContainerInjectionInterface;
use Drupal\Core\Form\FormBase;
use Drupal\Core\Form\FormInterface;
use Drupal\Core\Form\FormStateInterface;
use Drupal\Component\Utility\UrlHelper;
use Drupal\Core\Ajax\AjaxResponse;
use Drupal\Core\Ajax\ChangedCommand;
use Drupal\Core\Ajax\CssCommand;
use Drupal\Core\Ajax\HtmlCommand;
use Drupal\Core\Ajax\InvokeCommand;

/**
 * Contribute form.
 */

class ContributeForm extends FormBase implements FormInterface{
    protected $accepted_domains = ['gmail.com', 'yahoo.com'];

    /**
     * {@inheritdoc}
     */
    public function getFormId() {
        return 'contact_form_contribute_form';
    }

    /**
     * {@inheritdoc}
     */

    public function buildForm(array $form, FormStateInterface $form_state) {

        $form['FullName'] = array(
            '#type' =&gt; 'textfield',
            '#title' =&gt; $this-&gt;t('Full Name'),
            '#required' =&gt; TRUE,

        );
        $form['Email'] = array(
            '#type' =&gt; 'email',
            '#title' =&gt; $this-&gt;t('Email address'),
            '#required' =&gt; true,
            '#size' =&gt; 60,
            '#maxlength' =&gt; 128,

        );

        $form['Feedback'] = array(
            '#type' =&gt; 'radios',
            '#title' =&gt; $this-&gt;t('Feedback'),
            '#description' =&gt; t('Type of feedback'),
            '#default_value' =&gt; 0,
            '#options' =&gt; array(
                0 =&gt;'Comments or suggestions',
                1 =&gt; 'Questions',
                2 =&gt;'Report a problem(s)',
                3 =&gt;'Other',
            )
        );
        $form['Subject'] = array(
            '#type' =&gt; 'textfield',
            '#title' =&gt; $this-&gt;t('Subject'),
            '#required' =&gt; true,
        );
        $form['Message'] = array(
            '#type' =&gt; 'textarea',
            '#title' =&gt; $this-&gt;t('Your Message'),
            '#required' =&gt; true,
            '#cols' =&gt; 90,
            '#rows' =&gt; 10,
        );

        $form['captcha'] = array(
            '#type' =&gt; 'captcha',
            '#captcha_type' =&gt; 'recaptcha/reCAPTCHA',
            '#title' =&gt; $this-&gt;t('Captcha:'),
            '#required' =&gt; true,
        );

        $form['save'] = array(
            '#type' =&gt; 'submit',
            '#input' =&gt; TRUE,
            '#value' =&gt; 'save',
            '#submit' =&gt; array('buildForm')
        );


        return array(
            '#form' =&gt; $form,
            '#theme' =&gt; 'contribute',


        );

    }

    /**
     * {@inheritdoc}
     */

    public function validateForm(array &amp;$form, FormStateInterface $form_state) {
    }

    /**
     * {@inheritdoc}
     */
    public function submitForm(array &amp;$form, FormStateInterface $form_state) {
        $name = $form_state-&gt;getValue('FullName');
        $email = $form_state-&gt;getValue('Email');
        $subject = $form_state-&gt;getValue('Subject');
        $type = $form_state-&gt;getValue('TypeFeedback');
        $msg = $form_state-&gt;getValue('Message');
        $field = array(

            'FullName' =&gt;  $name,
            'Email' =&gt; $email,
            'TypeFeedback' =&gt;  $type ,
            'Subject' =&gt; $subject,
            'Message' =&gt;  $msg,
            'Etat_message'=&gt;  '',
            'Date_contact'=&gt;  '',
            'adresse_IP'=&gt;  '',
        );
        db_insert('contact')
            -&gt;fields($field)
            -&gt;execute();
        drupal_set_message("succesfully saved");


    }
}
Removing the #submit key fixed the submission issue for me:

$form['save'] = array(
    '#type' =&gt; 'submit',
    '#input' =&gt; TRUE,
    '#value' =&gt; 'save',
    //'#submit' =&gt; array('buildForm')
);


DB insert works correctly.

If you do return $form; in the buildForm() method, the radios form element is rendered correctly. Looks like your theme might be causing the issue.