Add instalments in product page

woocommerceinstalments.php

<?php
add_action( 'woocommerce_single_product_summary', 'woocommerce_total_product_price', 31 );
function woocommerce_total_product_price() {
    global $woocommerce, $product;
    // let's setup our divs
    echo sprintf('<div id="product_total_price" style="margin-bottom:20px;display:none">%s %s</div>','Total do Produto','<span class="price">'.$product->get_price().'</span>');
    echo sprintf('<div id="cart_total_price" style="margin-bottom:20px;display:none">%s %s</div>','Total do Carrinho','<span class="price">'.$product->get_price().'</span>');
    ?>
        <script>
            jQuery(function($){
                var price = <?php echo $product->get_price(); ?>,
                    current_cart_total = <?php echo $woocommerce->cart->cart_contents_total; ?>,
                    currency = '<?php echo get_woocommerce_currency_symbol(); ?>';
 
                $('[name=quantity]').change(function(){
                    if (!(this.value < 1)) {
                        var product_total = parseFloat(price * this.value),
                        cart_total = parseFloat(product_total + current_cart_total);
 
                        $('#product_total_price .price').html( currency + product_total.toFixed(2));
                        $('#cart_total_price .price').html( currency + cart_total.toFixed(2));

			var coef = [1, 0.52255, 0.35347, 0.26898, 0.21830, 0.18453,0.16044, 0.14240, 0.12838,0.11717, 0.10802, 0.10040];
			$('#parcel_1 .woocommerce-Price-amount.amount').html( currency + (((product_total * coef[0]).toFixed(2)).replace('.',',')));
			$('#parcel_2 .woocommerce-Price-amount.amount').html( currency + (((product_total * coef[1]).toFixed(2)).replace('.',',')));
			$('#parcel_3 .woocommerce-Price-amount.amount').html( currency + (((product_total * coef[2]).toFixed(2)).replace('.',',')));
			$('#parcel_4 .woocommerce-Price-amount.amount').html( currency + (((product_total * coef[3]).toFixed(2)).replace('.',',')));
			$('#parcel_5 .woocommerce-Price-amount.amount').html( currency + (((product_total * coef[4]).toFixed(2)).replace('.',',')));
			$('#parcel_6 .woocommerce-Price-amount.amount').html( currency + (((product_total * coef[5]).toFixed(2)).replace('.',',')));
			$('#parcel_7 .woocommerce-Price-amount.amount').html( currency + (((product_total * coef[6]).toFixed(2)).replace('.',',')));
			$('#parcel_8 .woocommerce-Price-amount.amount').html( currency + (((product_total * coef[7]).toFixed(2)).replace('.',',')));
			$('#parcel_9 .woocommerce-Price-amount.amount').html( currency + (((product_total * coef[8]).toFixed(2)).replace('.',',')));
			$('#parcel_10 .woocommerce-Price-amount.amount').html( currency + (((product_total * coef[9]).toFixed(2)).replace('.',',')));
			$('#parcel_11 .woocommerce-Price-amount.amount').html( currency + (((product_total * coef[10]).toFixed(2)).replace('.',',')));
			$('#parcel_12 .woocommerce-Price-amount.amount').html( currency + (((product_total * coef[11]).toFixed(2)).replace('.',',')));
                    }
                    $('#product_total_price,#cart_total_price').toggle(!(this.value < 1));
 
                });
            });
        </script>
    <?php
}

@cleucimar inclui no function.php

Tentei ir lá no editar tema e colocar no function, mas não funcionou com o método de pagamento que eu tenho (ASAAS), sabe se pode ser alguma coisa do tipo?

O método de pagamento estava configurado para parcelamento em até 5 vezes.

@murilopratavieira esse código inclui as parcelas no sumário do produto, independente do método de pagamento. Precisa ajustar os coeficientes de correção das parcelas ali na linha 23, de acordo com as suas taxas. Se não está aparecendo provavelmente é por causa do tema ou algum outro plugin que usa o hook woocommerce_single_product_summary