If you are in Cuba, you can get a recharge in two ways.
Request a recharge
How? Choose to recharge a cell line or Nauta WiFi account and click on the button "Request a Recharge".
Advantage: It is very easy for those who open that link because the number or Nauta account written on it will appear on the recharge screen.
If you want to know how to order these recharges, I recommend you check this article.
How? You can recharge from Cuba if you already have a card or Paypal account registered at Fonoma. If you haven't registered a payment method then most likely you will not be able to recharge. In this case, you'll have to use a free VPN service. Check out these recommendations.
Advantage: You will be able to take full advantage of Cubacel promotions, safely and without intermediaries.