submit button not working correctly To fix the problem with the submit function 
I have tried clearing my cache
I have also tried uninstalling the module and reinstalling the module. the code segment is below.

The submit function for some reason never is run

function redirect_custom_reg_menu_alter(&amp;$items) {
  if (isset($items['user/register'])) {
    $items['user/register']['page arguments'] = array('redirect_custom_reg_user_register_form');
  }
}

function redirect_custom_reg_user_register_form() {
  $form = array();

  // Add the form fields for the registration form.

  $form['personal']['username'] = array(
    '#type' =&gt; 'textfield',
    '#title' =&gt; t('username'), 
    // this is built in validation to the form api
    '#required' =&gt; TRUE, 
    // control the size parameter
    '#size' =&gt; 20,
    '#prefix' =&gt; '&lt;div id="foo"&gt;',
    '#suffix' =&gt; '&lt;/div&gt;',
    '#description' =&gt; 'Please enter your first name',
    '#maxlength' =&gt; 25,
  );

  $form['name']['formtype'] = array(
    '#type' =&gt; 'radios',
    '#title' =&gt; t('form type'),
    '#options' =&gt; array(
      t('form1 form'),
      t('form2 form'),
      t('form3 form')
    ),
  );

  $form['submit'] = array(
    '#type' =&gt; 'submit',
    '#value' =&gt; 'Submit',
  );

  return $form;
}

function redirect_custom_reg_submit($form, &amp;$form_state) {
  drupal_set_message(t('The form has been submitted. personal="@username"',
    array('@username' =&gt; $form_state['values']['username'] )));
}
Your form function is called redirect_custom_reg_user_register_form(), so your submit function needs to be called redirect_custom_reg_user_register_form_submit().

If you want to keep the same submit function name that you have currently, you need to add it manually in the form function as Drupal only looks for a function called FORM_FUNCTION_NAME_submit() by default:

$form['#submit'][] = 'redirect_custom_reg_submit';