diff --git a/services/appflowy-collaborate/src/group/group_init.rs b/services/appflowy-collaborate/src/group/group_init.rs
index aedcd6d1..c05cc63b 100644
--- a/services/appflowy-collaborate/src/group/group_init.rs
+++ b/services/appflowy-collaborate/src/group/group_init.rs
@@ -673,20 +673,34 @@ impl CollabGroup {
       .await
       .map_err(|err| RTProtocolError::Internal(err.into()))??
     };
-    let state_vector = decoded_update.state_vector();
-    state
-      .persister
-      .send_update(origin.clone(), update, state_vector)
-      .await
-      .map_err(|err| RTProtocolError::Internal(err.into()))?;
-    let elapsed = start.elapsed();
+    let missing_updates = {
+      let state_vector = state.state_vector.read().await;
+      match state_vector.partial_cmp(&decoded_update.state_vector_lower()) {
+        None | Some(std::cmp::Ordering::Less) => Some(state_vector.clone()),
+        _ => None,
+      }
+    };
 
-    state
-      .metrics
-      .apply_update_time
-      .observe(elapsed.as_millis() as f64);
+    if let Some(missing_updates) = missing_updates {
+      let msg = Message::Sync(SyncMessage::SyncStep1(missing_updates));
+      tracing::debug!("subscriber {} send update with missing data", origin);
+      Ok(Some(msg.encode_v1()))
+    } else {
+      let upper_state_vector = decoded_update.state_vector();
+      state
+        .persister
+        .send_update(origin.clone(), update, upper_state_vector)
+        .await
+        .map_err(|err| RTProtocolError::Internal(err.into()))?;
+      let elapsed = start.elapsed();
 
-    Ok(None)
+      state
+        .metrics
+        .apply_update_time
+        .observe(elapsed.as_millis() as f64);
+
+      Ok(None)
+    }
   }
 
   async fn handle_update(