diff --git a/src/transaction/client.rs b/src/transaction/client.rs
index 96718cab..eb9cc91b 100644
--- a/src/transaction/client.rs
+++ b/src/transaction/client.rs
@@ -278,6 +278,8 @@ impl Client {
         range: impl Into<BoundRange>,
         batch_size: u32,
     ) -> Result<Vec<crate::proto::kvrpcpb::LockInfo>> {
+        use crate::request::TruncateKeyspace;
+
         let range = range.into().encode_keyspace(self.keyspace, KeyMode::Txn);
         let req = new_scan_lock_request(range, safepoint, batch_size);
         let plan = crate::request::PlanBuilder::new(self.pd.clone(), self.keyspace, req)
diff --git a/tests/common/mod.rs b/tests/common/mod.rs
index 497d2493..d22a4cb1 100644
--- a/tests/common/mod.rs
+++ b/tests/common/mod.rs
@@ -24,17 +24,11 @@ const REGION_SPLIT_TIME_LIMIT: Duration = Duration::from_secs(15);
 
 // Delete all entries in TiKV to leave a clean space for following tests.
 pub async fn clear_tikv() {
-    // DEFAULT_REGION_BACKOFF is not long enough for CI environment. So set a longer backoff.
-    let backoff = tikv_client::Backoff::no_jitter_backoff(100, 30000, 20);
     let raw_client =
         RawClient::new_with_config(pd_addrs(), Config::default().with_default_keyspace())
             .await
             .unwrap();
-    raw_client
-        // .with_backoff(backoff.clone())
-        .delete_range(..)
-        .await
-        .unwrap();
+    raw_client.delete_range(..).await.unwrap();
 
     let txn_client =
         TransactionClient::new_with_config(pd_addrs(), Config::default().with_default_keyspace())