diff --git a/eco-core/core-plugin/src/main/kotlin/com/willfp/eco/internal/spigot/display/PacketWindowItems.kt b/eco-core/core-plugin/src/main/kotlin/com/willfp/eco/internal/spigot/display/PacketWindowItems.kt
index 876ac860..4aa53ed4 100644
--- a/eco-core/core-plugin/src/main/kotlin/com/willfp/eco/internal/spigot/display/PacketWindowItems.kt
+++ b/eco-core/core-plugin/src/main/kotlin/com/willfp/eco/internal/spigot/display/PacketWindowItems.kt
@@ -48,7 +48,7 @@ class PacketWindowItems(plugin: EcoPlugin) : AbstractPacketAdapter(plugin, Packe
         handleRateLimit(player)
 
         if (usingAsync(player)) {
-            val newPacket = packet.shallowClone()
+            val newPacket = packet.deepClone()
 
             executor.execute {
                 runCatchingWithLogs { modifyAndSend(newPacket, itemStacks, windowId, player) }