diff --git a/main-site/contact-form.js b/main-site/contact-form.js
index 5cfb022..7f04624 100644
--- a/main-site/contact-form.js
+++ b/main-site/contact-form.js
@@ -141,13 +141,15 @@
       return;
     }
 
-    const altchaWidget = form.querySelector('altcha-widget');
-    const altchaValue  = altchaWidget ? altchaWidget.value : '';
+    const errAltcha = document.getElementById('err-altcha');
+    if (errAltcha) errAltcha.style.display = 'none';
+
+    const altchaInput = form.querySelector('[name="altcha"]');
+    const altchaValue = altchaInput?.value || '';
     if (!altchaValue) {
-      const errEl = document.getElementById('err-altcha');
-      if (errEl) { errEl.style.display = ''; }
+      if (errAltcha) errAltcha.style.display = '';
       showAlert('Please complete the verification.', 'is-warning');
-      altchaWidget && altchaWidget.scrollIntoView({ behavior: 'smooth', block: 'center' });
+      form.querySelector('altcha-widget')?.scrollIntoView({ behavior: 'smooth', block: 'center' });
       return;
     }
 
diff --git a/main-site/contact/index.html b/main-site/contact/index.html
index 3107073..adb28b7 100644
--- a/main-site/contact/index.html
+++ b/main-site/contact/index.html
@@ -145,7 +145,7 @@
 
       <div class="field">
         <altcha-widget
-          challengeurl="/api/altcha"
+          challenge="/api/altcha"
           style="--altcha-color-border: #dbdbdb; --altcha-border-radius: 4px; --altcha-color-text: #363636;"
         ></altcha-widget>
         <p class="help is-danger" id="err-altcha" style="display:none;">Please complete the verification.</p>
diff --git a/main-site/index.html b/main-site/index.html
index a3046d6..55b0e54 100644
--- a/main-site/index.html
+++ b/main-site/index.html
@@ -220,7 +220,7 @@
 
     <div class="field">
       <altcha-widget
-        challengeurl="/api/altcha"
+        challenge="/api/altcha"
         style="--altcha-color-border: #dbdbdb; --altcha-border-radius: 4px; --altcha-color-text: #363636;"
       ></altcha-widget>
       <p class="help is-danger" id="err-altcha" style="display:none;">Please complete the verification.</p>