diff --git a/Lib9c.Policy/NCStagePolicy.cs b/Lib9c.Policy/NCStagePolicy.cs
index d8467e0643..d64e0ac66a 100644
--- a/Lib9c.Policy/NCStagePolicy.cs
+++ b/Lib9c.Policy/NCStagePolicy.cs
@@ -50,73 +50,96 @@ public bool Ignores(BlockChain blockChain, TxId id)
 
         public IEnumerable<Transaction> Iterate(BlockChain blockChain, bool filtered = true)
         {
-            if (filtered)
+            try
             {
-                var txsPerSigner = new Dictionary<Address, SortedSet<Transaction>>();
-                foreach (Transaction tx in _impl.Iterate(blockChain, filtered))
-                {
-                    if (!txsPerSigner.TryGetValue(tx.Signer, out var s))
-                    {
-                        txsPerSigner[tx.Signer] = s = new SortedSet<Transaction>(new TxComparer());
-                    }
-
-                    s.Add(tx);
-                    int txQuotaPerSigner = _quotaPerSigner;
-
-                    // update txQuotaPerSigner if signer is in the list
-                    if (_quotaPerSignerList.TryGetValue(tx.Signer, out int signerQuota))
-                    {
-                        Console.WriteLine("[TEST-QUOTA] ITERATE1 {0} quota: {1}", tx.Signer, signerQuota);
-                        txQuotaPerSigner = signerQuota;
-                    }
 
-                    if (_quotaPerSignerList.ContainsKey(tx.Signer))
+                if (filtered)
+                {
+                    var txsPerSigner = new Dictionary<Address, SortedSet<Transaction>>();
+                    foreach (Transaction tx in _impl.Iterate(blockChain, filtered))
                     {
-                        Console.WriteLine("[TEST-QUOTA] ITERATE2 {0} quota: {1}", tx.Signer, _quotaPerSignerList[tx.Signer]);
-                        txQuotaPerSigner = _quotaPerSignerList[tx.Signer];
+                        if (!txsPerSigner.TryGetValue(tx.Signer, out var s))
+                        {
+                            txsPerSigner[tx.Signer] =
+                                s = new SortedSet<Transaction>(new TxComparer());
+                        }
+
+                        s.Add(tx);
+                        int txQuotaPerSigner = _quotaPerSigner;
+
+                        // update txQuotaPerSigner if signer is in the list
+                        if (_quotaPerSignerList.TryGetValue(tx.Signer, out int signerQuota))
+                        {
+                            Console.WriteLine("[TEST-QUOTA] ITERATE1 {0} quota: {1}", tx.Signer,
+                                signerQuota);
+                            txQuotaPerSigner = signerQuota;
+                        }
+
+                        if (_quotaPerSignerList.ContainsKey(tx.Signer))
+                        {
+                            Console.WriteLine("[TEST-QUOTA] ITERATE2 {0} quota: {1}", tx.Signer,
+                                _quotaPerSignerList[tx.Signer]);
+                            txQuotaPerSigner = _quotaPerSignerList[tx.Signer];
+                        }
+
+                        if (s.Count > txQuotaPerSigner)
+                        {
+                            s.Remove(s.Max);
+                        }
                     }
 
-                    if (s.Count > txQuotaPerSigner)
-                    {
-                        s.Remove(s.Max);
-                    }
-                }
-
 #pragma warning disable LAA1002 // DictionariesOrSetsShouldBeOrderedToEnumerate
-                return txsPerSigner.Values.SelectMany(i => i);
+                    return txsPerSigner.Values.SelectMany(i => i);
 #pragma warning restore LAA1002 // DictionariesOrSetsShouldBeOrderedToEnumerate
+                }
+                else
+                {
+                    return _impl.Iterate(blockChain, filtered);
+                }
             }
-            else
+            catch (Exception ex)
             {
+                Console.WriteLine("[TEST-QUOTA] ITERATE: {0}", ex.Message);
+                Console.WriteLine("[TEST-QUOTA] ITERATE: {0}", ex.StackTrace);
                 return _impl.Iterate(blockChain, filtered);
             }
         }
 
         public bool Stage(BlockChain blockChain, Transaction transaction)
         {
-            if (_accessControlService?.GetTxQuota(transaction.Signer) is { } acsTxQuota)
+            try
             {
-                Console.WriteLine("[TEST-QUOTA] STAGE {0} quota: {1}", transaction.Signer, acsTxQuota);
-                _quotaPerSignerList.Add(transaction.Signer, acsTxQuota);
-                if (acsTxQuota == 0)
+
+                if (_accessControlService?.GetTxQuota(transaction.Signer) is { } acsTxQuota)
+                {
+                    Console.WriteLine("[TEST-QUOTA] STAGE {0} quota: {1}", transaction.Signer, acsTxQuota);
+                    _quotaPerSignerList.Add(transaction.Signer, acsTxQuota);
+                    if (acsTxQuota == 0)
+                    {
+                        return false;
+                    }
+                }
+
+                var deniedTxs = new[]
+                {
+                    // CreatePledge Transaction with 50000 addresses
+                    TxId.FromHex("300826da62b595d8cd663dadf04995a7411534d1cdc17dac75ce88754472f774"),
+                    // CreatePledge Transaction with 5000 addresses
+                    TxId.FromHex("210d1374d8f068de657de6b991e63888da9cadbc68e505ac917b35568b5340f8"),
+                };
+                if (deniedTxs.Contains(transaction.Id))
                 {
                     return false;
                 }
-            }
 
-            var deniedTxs = new[]
-            {
-                // CreatePledge Transaction with 50000 addresses
-                TxId.FromHex("300826da62b595d8cd663dadf04995a7411534d1cdc17dac75ce88754472f774"),
-                // CreatePledge Transaction with 5000 addresses
-                TxId.FromHex("210d1374d8f068de657de6b991e63888da9cadbc68e505ac917b35568b5340f8"),
-            };
-            if (deniedTxs.Contains(transaction.Id))
+                return _impl.Stage(blockChain, transaction);
+            }
+            catch (Exception ex)
             {
-                return false;
+                Console.WriteLine("[TEST-QUOTA] STAGE: {0}", ex.Message);
+                Console.WriteLine("[TEST-QUOTA] STAGE: {0}", ex.StackTrace);
+                return _impl.Stage(blockChain, transaction);
             }
-
-            return _impl.Stage(blockChain, transaction);
         }
 
         public bool Unstage(BlockChain blockChain, TxId id)