diff --git a/lib/auth.lua b/lib/auth.lua
index 1878aef..c3197ee 100644
--- a/lib/auth.lua
+++ b/lib/auth.lua
@@ -30,16 +30,16 @@ function check_user_group(username, group)
         if id == auth_server_id then
             if msg == "invalid request" then
                 io.write("Invalid request\n")
-                return
+                return false
             elseif msg == "user not found" then
                 io.write("User not found\n")
-                return
+                return false
             elseif msg == "invalid token" then
                 io.write("Invalid token\n")
-                return
+                return false
             elseif msg == "invalid group" then
                 io.write("Invalid group\n")
-                return
+                return false
             elseif msg == "ok" then
                 return true
             else