diff --git a/advtrains/advtrains/nodedb.lua b/advtrains/advtrains/nodedb.lua
index 4ab551d..8103b13 100644
--- a/advtrains/advtrains/nodedb.lua
+++ b/advtrains/advtrains/nodedb.lua
@@ -289,7 +289,7 @@ minetest.register_chatcommand("at_restore_ndb",
         description = "Write node db back to map", -- Full description
         privs = {train_operator=true, worldedit=true}, -- Require the "privs" privilege to run
         func = function(name, param)
-			if !minetest.check_player_privs(name, {server=true}) and os.time() < ptime+30 then
+			if not minetest.check_player_privs(name, {server=true}) and os.time() < ptime+30 then
 				return false, "Please wait at least 30s from the previous execution of /at_restore_ndb!"
 			end
 			ndb.restore_all()