diff --git a/html/pfappserver/root/src/views/Configuration/portalModules/schema.js b/html/pfappserver/root/src/views/Configuration/portalModules/schema.js
index a0a3afacf523..d23cb2450b92 100644
--- a/html/pfappserver/root/src/views/Configuration/portalModules/schema.js
+++ b/html/pfappserver/root/src/views/Configuration/portalModules/schema.js
@@ -47,7 +47,7 @@ export const schema = (props) => {
     ssl_mobileconfig_path: yup.string().label(i18n.t('URL')),
     ssl_path: yup.string().label(i18n.t('URL')),
     url: yup.string().nullable().label(i18n.t('URL')),
-    username: yup.string().label(i18n.t('Username'))
+    username: yup.string().nullable().label(i18n.t('Username'))
   })
 }