diff --git a/components/NewGameBan.tsx b/components/NewGameBan.tsx
index 6ca125b..77b98b0 100644
--- a/components/NewGameBan.tsx
+++ b/components/NewGameBan.tsx
@@ -48,6 +48,9 @@ export default function(props: { isOpen: boolean; onClose: () => void }) {
   function addUser(user: string) {
     const newUsers = [...users];
 
+    if (newUsers.includes(user))
+      return;
+
     newUsers.push(user);
     setUsers(newUsers);
   }