You can update your payment method by logging into your Enscape account.
If you hover over your account name in the right-hand corner, you can select "payment method" to change your payment method. If you hover over your account name in the right-hand corner you can select "Invoices", which will lead you to the invoice page.
You can then pay the entire balance by pressing the "Pay Now" button in the Overall Balance box and following the steps to payment.
Alternatively, you can pay individually by selecting the box next to each invoice. Once selected, you will see a "Pay Now" button appear at the bottom right corner. You can click that button and follow the steps to payment.
Once processed successfully, you will notice that the invoice(s) will be listed as "paid".