diff --git a/src/network/mcpe/handler/ItemStackRequestExecutor.php b/src/network/mcpe/handler/ItemStackRequestExecutor.php
index bdc2937a5..840a23cc1 100644
--- a/src/network/mcpe/handler/ItemStackRequestExecutor.php
+++ b/src/network/mcpe/handler/ItemStackRequestExecutor.php
@@ -113,7 +113,12 @@ class ItemStackRequestExecutor{
 	 */
 	protected function getBuilderInventoryAndSlot(ItemStackRequestSlotInfo $info) : array{
 		$windowId = ItemStackContainerIdTranslator::translate($info->getContainerId(), $this->inventoryManager->getCurrentWindowId());
-		$windowAndSlot = $this->inventoryManager->locateWindowAndSlot($windowId, $info->getSlotId());
+		$slotId = $info->getSlotId();
+		if($info->getContainerId() === ContainerUIIds::OFFHAND && $slotId === 1){
+			//TODO: HACK! The client sends an incorrect slot ID for the offhand as of 1.19.70
+			$slotId = 0;
+		}
+		$windowAndSlot = $this->inventoryManager->locateWindowAndSlot($windowId, $slotId);
 		if($windowAndSlot === null){
 			throw new ItemStackRequestProcessException("No open inventory matches container UI ID: " . $info->getContainerId() . ", slot ID: " . $info->getSlotId());
 		}
diff --git a/src/network/mcpe/handler/ItemStackResponseBuilder.php b/src/network/mcpe/handler/ItemStackResponseBuilder.php
index 68a549f21..2a55c2d95 100644
--- a/src/network/mcpe/handler/ItemStackResponseBuilder.php
+++ b/src/network/mcpe/handler/ItemStackResponseBuilder.php
@@ -53,6 +53,10 @@ final class ItemStackResponseBuilder{
 	 * @phpstan-return array{Inventory, int}
 	 */
 	private function getInventoryAndSlot(int $containerInterfaceId, int $slotId) : ?array{
+		if($containerInterfaceId === ContainerUIIds::OFFHAND && $slotId === 1){
+			//TODO: HACK! The client sends an incorrect slot ID for the offhand as of 1.19.70
+			$slotId = 0;
+		}
 		$windowId = ItemStackContainerIdTranslator::translate($containerInterfaceId, $this->inventoryManager->getCurrentWindowId());
 		$windowAndSlot = $this->inventoryManager->locateWindowAndSlot($windowId, $slotId);
 		if($windowAndSlot === null){