diff --git a/frontend/src/validation-rules.js b/frontend/src/validation-rules.js
index 8d2c7d397..d75ca6dc3 100644
--- a/frontend/src/validation-rules.js
+++ b/frontend/src/validation-rules.js
@@ -148,7 +148,7 @@ export const loadAllRules = (i18nCallback, apollo) => {
 
   extend('usernameUnique', {
     validate(value) {
-      if (!value.match(usernameRegex)) return true
+      if (!value.match(USERNAME_REGEX)) return true
       return apollo
         .query({
           query: checkUsername,