problem with pricing

Hello. Help me to understand. I use wordpress + woocommerce + wc-fields-factory + Exchange Rates Today
(Exchange Rates Today) changes the price from the rate entered manually.
There was a problem with wc-fields-factory + Exchange Rates Today in conjunction. I set the price in the Exchange Rates Today plugin (1.16%) and in the shopping cart the price increases 2 times by 1.16%, and should increase 1 time by (1.16%).

Having searched a little better, I found what the code swears at,wc-fields-factory\includes\wcff-negotiator.php line 73.

							} else {
								if ($prule ["ptype"] == "add") {
									$percentage_price = $percentage_price + ( ( floatval ( $prule ["amount"] ) / 100 ) * $basePrice);
								} else {
									$customPrice = 0;
									$percentage_price = (floatval ($prule ["amount"] ) / 100) * $basePrice;
								}
							}

This is the Exchange Rates Today plugin code

<?php
/**
 * @package Exchange Rates Today
 * @version 1.7
 */
/*
Plugin Name: Exchange Rates Today
Plugin URI: http://silver.od.ua
Description: A simple plugin for WooCommerce that allows you to change the price according to the exchange rate. For example, you set the price on the website in dollars and in-store price is displayed in local currency, you simply are asking today's exchange rate, but the plugin automatically changes all prices.
Author: Artyom Lagondyuk
Version: 1.7
Author URI: http://silver.od.ua
*/

add_action ('admin_menu', 'dynamic_price_button');
//Simple product
add_filter('woocommerce_product_get_price', 'custom_price', 99, 2 );
add_filter('woocommerce_product_get_regular_price', 'custom_price', 99, 2 );
add_filter( 'woocommerce_price_filter_widget_min_amount', 'custom_price', 99, 2);
add_filter( 'woocommerce_price_filter_widget_max_amount', 'custom_price', 99, 2);
// Variable
add_filter('woocommerce_product_variation_get_regular_price', 'custom_price', 99, 2 );
add_filter('woocommerce_product_variation_get_price', 'custom_price', 99, 2 );
// Variations
add_filter('woocommerce_variation_prices_price', 'custom_price', 99, 3 );
add_filter('woocommerce_variation_prices_regular_price', 'custom_price', 99, 3 );
add_filter( 'woocommerce_variation_prices_sale_price',    'custom_price', 99, 3  );
// Handling price caching (see explanations at the end)
add_filter( 'woocommerce_get_variation_prices_hash', 'add_price_multiplier_to_variation_prices_hash', 99, 1 );

add_action( 'admin_init', 'register_mysettings' );

function register_mysettings () {
    register_setting( 'baw-settings-group', 'kurs' );
    register_setting( 'baw-settings-group', 'valuta' );
}

function custom_price ($price) {
    $int = floatval($price);
    $kurs=get_option('kurs');
    if ($kurs!='') {
        return $int*$kurs;
    } else  return  $int;
}

function add_price_multiplier_to_variation_prices_hash($hash){
    $hash[] = get_option('kurs');
    return $hash;
}

function dynamic_price_button () {
    add_submenu_page ('woocommerce', 'Курс сегодня', 'Курс сегодня', 'manage_options', 'dynamic_price', 'setting_page');
}

function setting_page () {
?>
<div class="wrap">
<h2>Курс на сегодня</h2>
<form method="post" action="options.php">
    <?php settings_fields( 'baw-settings-group' ); ?>
    <table class="form-table">
        <tr valign="top">
        <th scope="row">РљСѓСЂСЃ</th>
        <td><input type="text" name="kurs" value="<?php echo get_option('kurs'); ?>" /></td>
        </tr>               
    </table>
    
    <p class="submit">
    <input type="submit" class="button-primary" value="<?php _e('Save Changes') ?>" />
    </p>

</form>
</div>
<?php }

add_filter( 'woocommerce_product_query_meta_query', 'filter_function_name_3276', 10, 2 );
function filter_function_name_3276( $meta_query ){
    if ( isset( $_GET['max_price'] ) || isset( $_GET['min_price'] ) ) { // WPCS: input var ok, CSRF ok.
            $kurs=get_option('kurs');
            if (isset($_GET['min_price']) && $_GET['min_price']>0){
                $meta_query['price_filter']['value'][0] =  $meta_query['price_filter']['value'][0]/$kurs;
            };
            if (isset($_GET['max_price'])){
                $meta_query['price_filter']['value'][1] =  $meta_query['price_filter']['value'][1]/$kurs;
            };
            return $meta_query;
    }
    return $meta_query;
}

I understand that the second plugin is not yours, please help with the code, or at least tell me where the problem is. Thanks in advance =)