diff --git a/src/actions/DinerAction.lua b/src/actions/DinerAction.lua
index b4e88bd..37c1a24 100644
--- a/src/actions/DinerAction.lua
+++ b/src/actions/DinerAction.lua
@@ -46,8 +46,8 @@ function _M.addSellRpc( agent, data )
 		end
 
 		local cost = dishData.material:toNumMap()
-		for _, n in pairs(cost) do
-			n = n * count
+		for k, n in pairs(cost) do
+			cost[k] = n * count
 		end
 		if not role:checkItemEnough(cost) then
 			return 6
--
libgit2 0.21.2