diff --git a/crates/loro-internal/src/log_store/import.rs b/crates/loro-internal/src/log_store/import.rs
index 6fa5ca92..de837469 100644
--- a/crates/loro-internal/src/log_store/import.rs
+++ b/crates/loro-internal/src/log_store/import.rs
@@ -371,10 +371,13 @@ impl LogStore {
                 self.try_apply_pending(&client_id, &mut latest_vv, &mut retain_changes)
             }
         } else {
+            // Changes will be sorted by lamport. If the first change cannot be applied, then all subsequent changes with the same client id cannot be applied either.
+            // we cache these client id.
             let mut pending_clients = FxHashSet::default();
             changes
                 .into_values()
                 .flat_map(|c| c.into_iter())
+                // sort changes by lamport from small to large
                 .sorted_by(|a, b| Ord::cmp(&b.lamport, &a.lamport))
                 .for_each(|c| {
                     let c_client_id = c.id.client_id;
@@ -385,7 +388,6 @@ impl LogStore {
                     match can_remote_change_be_applied(&latest_vv, &c) {
                         ChangeApplyState::Directly => {
                             latest_vv.set_end(c.id_end());
-                            // let last_id = c.id_last();
                             retain_changes
                                 .entry(c_client_id)
                                 .or_insert_with(Vec::new)
@@ -397,10 +399,10 @@ impl LogStore {
                             );
                         }
                         ChangeApplyState::Existing => {}
-                        ChangeApplyState::Future(dep) => {
+                        ChangeApplyState::Future(this_dep_client) => {
                             pending_clients.insert(c_client_id);
                             self.pending_changes
-                                .entry(dep.client_id)
+                                .entry(this_dep_client)
                                 .or_insert_with(Vec::new)
                                 .push(c);
                         }
@@ -438,9 +440,9 @@ impl LogStore {
                     ChangeApplyState::Existing => {
                         may_apply_iter.next();
                     }
-                    ChangeApplyState::Future(this_dep) => {
+                    ChangeApplyState::Future(this_dep_client) => {
                         self.pending_changes
-                            .entry(this_dep.client_id)
+                            .entry(this_dep_client)
                             .or_insert_with(Vec::new)
                             .extend(may_apply_iter);
                         break;
@@ -454,8 +456,8 @@ impl LogStore {
 enum ChangeApplyState {
     Existing,
     Directly,
-    /// The id of first missing dep
-    Future(ID),
+    /// The client id of first missing dep
+    Future(ClientID),
 }
 
 fn can_remote_change_be_applied(vv: &VersionVector, change: &Change<RemoteOp>) -> ChangeApplyState {
@@ -463,7 +465,7 @@ fn can_remote_change_be_applied(vv: &VersionVector, change: &Change<RemoteOp>) -
     let CounterSpan { start, end } = change.ctr_span();
     let vv_latest_ctr = vv.get(&change_client_id).copied().unwrap_or(0);
     if vv_latest_ctr < start {
-        return ChangeApplyState::Future(change.id.inc(-1));
+        return ChangeApplyState::Future(change_client_id);
     }
     if vv_latest_ctr >= end {
         return ChangeApplyState::Existing;
@@ -471,7 +473,7 @@ fn can_remote_change_be_applied(vv: &VersionVector, change: &Change<RemoteOp>) -
     for dep in &change.deps {
         let dep_vv_latest_ctr = vv.get(&dep.client_id).copied().unwrap_or(0);
         if dep_vv_latest_ctr - 1 < dep.counter {
-            return ChangeApplyState::Future(*dep);
+            return ChangeApplyState::Future(dep.client_id);
         }
     }
     ChangeApplyState::Directly