diff --git a/Lib9c b/Lib9c
index f5f370fc5..6e1fcdf48 160000
--- a/Lib9c
+++ b/Lib9c
@@ -1 +1 @@
-Subproject commit f5f370fc58a8ae9dfef63b1515c96ccffec3ae59
+Subproject commit 6e1fcdf488f7bcd11a8b84dd60e60208eafb5348
diff --git a/NineChronicles.Headless.Tests/GraphTypes/StandaloneMutationTest.cs b/NineChronicles.Headless.Tests/GraphTypes/StandaloneMutationTest.cs
index 1cd0808af..556a0deaa 100644
--- a/NineChronicles.Headless.Tests/GraphTypes/StandaloneMutationTest.cs
+++ b/NineChronicles.Headless.Tests/GraphTypes/StandaloneMutationTest.cs
@@ -903,14 +903,31 @@ public async Task StageTransaction()
             StandaloneContextFx.BlockChain = service.Swarm?.BlockChain;
 
             var pk = new PrivateKey();
-            ActionBase action = new ApprovePledge
+            ActionBase patronPrepareAction = new PrepareRewardAssets
             {
-                PatronAddress = new PrivateKey().Address
+                RewardPoolAddress = MeadConfig.PatronAddress,
+                Assets = new List<FungibleAssetValue>
+                {
+                    1 * Currencies.Mead,
+                },
             };
-            var tx = Transaction.Create(0, pk, BlockChain.Genesis.Hash, new[] { action.PlainValue });
+            var tx = Transaction.Create(0, pk, BlockChain.Genesis.Hash, new[] { patronPrepareAction.PlainValue });
             var payload = ByteUtil.Hex(tx.Serialize());
             var stageTxMutation = $"mutation {{ stageTransaction(payload: \"{payload}\") }}";
             var stageTxResult = await ExecuteQueryAsync(stageTxMutation);
+            Assert.Null(stageTxResult.Errors);
+
+            var block = service.BlockChain.ProposeBlock(ProposerPrivateKey, null);
+            service.BlockChain.Append(block, GenerateBlockCommit(1, block.Hash, new List<PrivateKey>() { ProposerPrivateKey }));
+
+            ActionBase action = new ApprovePledge
+            {
+                PatronAddress = new PrivateKey().Address
+            };
+            tx = Transaction.Create(0, pk, BlockChain.Genesis.Hash, new[] { action.PlainValue });
+            payload = ByteUtil.Hex(tx.Serialize());
+            stageTxMutation = $"mutation {{ stageTransaction(payload: \"{payload}\") }}";
+            stageTxResult = await ExecuteQueryAsync(stageTxMutation);
             var error = Assert.Single(stageTxResult.Errors!);
             Assert.Contains("gas", error.Message);
         }