diff --git a/packages/protocol/contracts/layer1/based/TaikoL1.sol b/packages/protocol/contracts/layer1/based/TaikoL1.sol
index 225a698ca6..c9bf899783 100644
--- a/packages/protocol/contracts/layer1/based/TaikoL1.sol
+++ b/packages/protocol/contracts/layer1/based/TaikoL1.sol
@@ -77,8 +77,10 @@ contract TaikoL1 is EssentialContract, ITaikoL1, TaikoEvents {
         returns (TaikoData.BlockMetadata memory meta_, TaikoData.EthDeposit[] memory deposits_)
     {
         TaikoData.Config memory config = getConfig();
-        (meta_,) = LibProposing.proposeBlock(state, config, this, _params, _txList);
-        if (meta_.id >= config.ontakeForkHeight) revert L1_FORK_ERROR();
+
+        TaikoData.BlockMetadataV2 memory metaV2;
+        (meta_, metaV2) = LibProposing.proposeBlock(state, config, this, _params, _txList);
+        if (metaV2.id >= config.ontakeForkHeight) revert L1_FORK_ERROR();
         deposits_ = new TaikoData.EthDeposit[](0);
     }