diff --git a/app/routes/et-members.tsx b/app/routes/et-members.tsx
index 69f0f0d..278e8f6 100644
--- a/app/routes/et-members.tsx
+++ b/app/routes/et-members.tsx
@@ -301,7 +301,8 @@ export default function () {
                 if (
                   data.match(/\W/) ||
                   data.length > 20 ||
-                  (data.match(/_/g)?.length || 0) > 1 ||
+                  // Need Number pseudo-constructor since matches might be null
+                  Number(data.match(/_/g)?.length) > 1 ||
                   data.startsWith("_")
                 )
                   e.preventDefault();