diff --git a/MarketService/ProductWorker.cs b/MarketService/ProductWorker.cs
index 02e4e6a..59a6d36 100644
--- a/MarketService/ProductWorker.cs
+++ b/MarketService/ProductWorker.cs
@@ -24,7 +24,16 @@ protected override async Task ExecuteAsync(CancellationToken stoppingToken)
             var stopWatch = new Stopwatch();
             _logger.LogInformation("[ProductWorker]Start sync product");
 
-            while (_rpcClient.Tip is null) await Task.Delay(100, stoppingToken);
+            var retry = 0;
+            while (_rpcClient.Tip?.Index == _rpcClient.PreviousTip?.Index)
+            {
+                await Task.Delay((5 - retry) * 1000, stoppingToken);
+                retry++;
+                if (retry >= 3)
+                {
+                    throw new InvalidOperationException();
+                }
+            }
 
             stopWatch.Start();
 
@@ -44,8 +53,8 @@ protected override async Task ExecuteAsync(CancellationToken stoppingToken)
 
             stopWatch.Stop();
             var ts = stopWatch.Elapsed;
-            await Task.Delay(1000, stoppingToken);
             _logger.LogInformation("[ProductWorker]Complete sync product on {BlockIndex}. {TotalElapsed}", _rpcClient.Tip.Index, ts);
+            await Task.Delay(8000, stoppingToken);
         }
     }
 }
diff --git a/MarketService/Receiver.cs b/MarketService/Receiver.cs
index 682fdce..2514d46 100644
--- a/MarketService/Receiver.cs
+++ b/MarketService/Receiver.cs
@@ -8,6 +8,7 @@ namespace MarketService;
 public class Receiver : IActionEvaluationHubReceiver
 {
     public Block Tip;
+    public Block PreviousTip;
     private readonly ILogger<Receiver> _logger;
     private readonly Codec _codec = new Codec();
 
@@ -28,6 +29,7 @@ public void OnRenderBlock(byte[] oldTip, byte[] newTip)
     {
         var dict = (Dictionary)_codec.Decode(newTip);
         var newTipBlock = BlockMarshaler.UnmarshalBlock(dict);
+        PreviousTip = Tip;
         Tip = newTipBlock;
     }
 
diff --git a/MarketService/RpcClient.cs b/MarketService/RpcClient.cs
index 82f9fbd..7a3e71c 100644
--- a/MarketService/RpcClient.cs
+++ b/MarketService/RpcClient.cs
@@ -59,6 +59,7 @@ public class RpcClient
 
     public bool Ready => _ready;
     public Block Tip => _receiver.Tip;
+    public Block PreviousTip => _receiver.PreviousTip;
 
 
     public RpcClient(IOptions<RpcConfigOptions> options, ILogger<RpcClient> logger, Receiver receiver,
diff --git a/MarketService/ShopWorker.cs b/MarketService/ShopWorker.cs
index a747841..6ee2fd9 100644
--- a/MarketService/ShopWorker.cs
+++ b/MarketService/ShopWorker.cs
@@ -27,9 +27,19 @@ protected override async Task ExecuteAsync(CancellationToken stoppingToken)
             if (stoppingToken.IsCancellationRequested) stoppingToken.ThrowIfCancellationRequested();
 
             var stopWatch = new Stopwatch();
-
-            while (_rpcClient.Tip is null) await Task.Delay(100, stoppingToken);
             _logger.LogInformation("Start sync shop");
+
+            var retry = 0;
+            while (_rpcClient.Tip?.Index == _rpcClient.PreviousTip?.Index)
+            {
+                await Task.Delay((5 - retry) * 1000, stoppingToken);
+                retry++;
+                if (retry >= 3)
+                {
+                    throw new InvalidOperationException();
+                }
+            }
+
             stopWatch.Start();
 
             var hashBytes = await _rpcClient.GetBlockStateRootHashBytes();