Add to cart ajax not working if user is logged in.

When you add the products to the cart when a user is logged in nothing happens but when you are not logged in it works.

I have deactivated all plugins and it still doesn’t work.

I cannot deactivate the theme as the functionality needed is within the theme’s code.

<?php
/**
 * Adds all selected and checked product items to the basket.
 */
function add_cb_to_cart() {
	global $woocommerce;
	$selectedProductArray = $_POST['selected_product_array'];
	$checkedProductArray  = $_POST['checked_product_array'];
	// Merge all products.
	$productArray = array_merge( (array) $selectedProductArray, (array) $checkedProductArray );
	// Loops over each product and add it to basket.
	foreach ( $productArray as $row ) {
		$row           = str_replace( '\"', '', $row );
		$productCartId = $woocommerce->cart->generate_cart_id( $row );
		$product = get_product( $row );
		if ( ! $woocommerce->cart->find_product_in_cart( $productCartId ) ) {
			// If the product is not in the cart then add it.
			if ($product->is_type( 'grouped' )) {
				$grouped_products = [];
				foreach( $product->get_children() as $children_id ){
		            $grouped_products[] = $children_id;
		        }
		        foreach ($grouped_products as $groupedRow) {
		        	$woocommerce->cart->add_to_cart( $groupedRow );
		        }
	        } else {
				$woocommerce->cart->add_to_cart( $row );
			}
		}
	}

	die();
}

add_action( 'wp_ajax_add_cb_to_cart', 'add_cb_to_cart' );
add_action( 'wp_ajax_nopriv_add_cb_to_cart', 'add_cb_to_cart' );
 add_action('woocommerce_before_cart','QuadLayers_apply_coupon_cart_values');

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