AJAX Search returns "You do not have sufficient permissions to access this page" on non-admin user - ajax

Question

I have this demo website that I'm making:
https://theme.artware.gr/
The problem I am facing is on the search functionality. You can click on the right/top side search to see the issue. When I am logged-in as admin, the search works fine, but when I view the page as a guest I get the error: "You do not have sufficient permissions to access this page".
This is my code so far:
// AJAX Search (no WooCommerce)
if ( !class_exists( 'WooCommerce' ) ) {
function simple_search_scripts(){
wp_enqueue_script( 'simple_search', get_stylesheet_directory_uri() . '/js/search.js', array(), '1.0.0', true);
wp_localize_script('simple_search', 'myAjax', array( 'ajaxurl' => admin_url( 'admin-ajax.php', 'relative' ), 'nonce' => wp_create_nonce('ajax-nonce') ));
}
// Create shortcode
function simple_search(){
simple_search_scripts(); ?>
<input type="text" name="keyword" id="keyword" onkeyup="fetch()" placeholder="<?php _e('Αναζήτηση...'); ?>" />
<div id="datafetch"></div>
<?php
}
add_shortcode('simple_search', 'simple_search');
// Fetch data
function simple_search_callback(){
$the_query = new WP_Query( array( 'posts_per_page' => 10, 's' => esc_attr( $_GET['keyword'] ), 'post_type' => 'post' ) );
if( $the_query->have_posts() ) : while( $the_query->have_posts() ) : $the_query->the_post();
$myquery = esc_attr( $_GET['keyword'] );
$a = $myquery;
$search = get_the_title();
if( stripos("/{$search}/", $a) !== false) { ?>
<div class="result-sin">
<?php $image = wp_get_attachment_image_src( get_post_thumbnail_id( $post->ID ), 'medium' ); ?>
<div class="result-sin-img">
<?php if ($image) { ?>
<img src="<?php echo $image[0]; ?>" width="<?php echo $image[1]; ?>" height="<?php echo $image[2]; ?>" />
<?php } ?>
</div>
<div class="result-sin-tit"><?php the_title();?></div>
<div class="result-sin-txt"><?php the_excerpt();?></div>
</div>
<?php }
endwhile;
wp_reset_postdata();
endif;
die();
}
add_action('wp_ajax_simple_search', 'simple_search_callback' );
add_action('wp_ajax_nopriv_simple_search', 'simple_search_callback' );
}
And the search.js:
function fetch(){
jQuery.ajax({
async: true,
url: myAjax.ajaxurl,
type: 'GET',
data: {
action: 'simple_search',
keyword: jQuery('#keyword').val(),
nonce: myAjax.nonce
},
success: function(data) {
jQuery('#datafetch').html( data );
}
});
}
And on the header, I simply call a shortcode [simple_search] . Everything post I read on SO said that the wp_ajax_nopriv_ACTION was missing. But I already have that.
UPDATE
I tried using method GET, that didn't work. I also used: wp_localize_script('simple_search', 'myAjax', array( 'ajaxurl' => admin_url( 'admin-ajax.php', 'relative' ), 'nonce' => wp_create_nonce('ajax-nonce') )); to better enqueue the admin-ajax.php, that didn't work either.

Answer 1

Somewhere In my theme I had require_once('file.php') that had the line below:
if ( !current_user_can( 'manage_options' ) ) { wp_die( __( 'You do not have sufficient permissions to access this page.' ) ); }
When I removed this, the problem was fixed.