diff --git a/pkg/tso/global_allocator.go b/pkg/tso/global_allocator.go
index 126cf8a0a613..040f2c299166 100644
--- a/pkg/tso/global_allocator.go
+++ b/pkg/tso/global_allocator.go
@@ -45,7 +45,11 @@ import (
 	"google.golang.org/grpc"
 )
 
-const ttlSeconds = 3
+const (
+	ttlSeconds          = 3
+	keyspaceGroupPrefix = "keyspace_group"
+	pdPrefix            = "pd"
+)
 
 // Allocator is a Timestamp Oracle allocator.
 type Allocator interface {
@@ -540,6 +544,9 @@ func (gta *GlobalTSOAllocator) getCurrentTSO(ctx context.Context) (*pdpb.Timesta
 func (gta *GlobalTSOAllocator) Reset() {
 	gta.tsoAllocatorRoleGauge.Set(0)
 	gta.timestampOracle.ResetTimestamp()
+	if err := gta.deregisterAllocator(); err != nil {
+		log.Warn("deregister tso allocator failed", zap.String("key", gta.am.allocatorKey), errs.ZapError(err))
+	}
 }
 
 // primaryElectionLoop is used to maintain the TSO primary election and TSO's
@@ -803,11 +810,15 @@ func (gta *GlobalTSOAllocator) register() (<-chan *clientv3.LeaseKeepAliveRespon
 	if err != nil {
 		return nil, true
 	}
+	allocatorKey := strings.TrimLeft(gta.am.allocatorKey, gta.am.allocatorKeyPrefix)
 	// wait for the previous allocator with different mode to be deregistered
 	if len(resp.Kvs) > 0 {
 		for _, kv := range resp.Kvs {
-			key := string(kv.Key)
-			if !strings.Contains(key, gta.am.allocatorKeyPrefix) {
+			key := strings.TrimLeft(string(kv.Key), gta.am.allocatorKeyPrefix)
+			if strings.Contains(allocatorKey, keyspaceGroupPrefix) && strings.Contains(key, pdPrefix) {
+				return nil, true
+			}
+			if strings.Contains(allocatorKey, pdPrefix) && strings.Contains(key, keyspaceGroupPrefix) {
 				return nil, true
 			}
 		}
diff --git a/pkg/tso/keyspace_group_manager.go b/pkg/tso/keyspace_group_manager.go
index 0993e94fb679..df34b9658749 100644
--- a/pkg/tso/keyspace_group_manager.go
+++ b/pkg/tso/keyspace_group_manager.go
@@ -1103,6 +1103,9 @@ func (kgm *KeyspaceGroupManager) HandleTSORequest(
 		if err != nil {
 			return err
 		}
+		if allocator.IsInitialize() {
+			return nil
+		}
 		// TODO: support the Local TSO Allocator.
 		return allocator.Initialize(0)
 	})
diff --git a/pkg/tso/keyspace_group_manager_test.go b/pkg/tso/keyspace_group_manager_test.go
index 029dd79d8eb0..6fa355b8310b 100644
--- a/pkg/tso/keyspace_group_manager_test.go
+++ b/pkg/tso/keyspace_group_manager_test.go
@@ -33,7 +33,9 @@ import (
 	"github.com/stretchr/testify/suite"
 	"github.com/tikv/pd/pkg/mcs/discovery"
 	"github.com/tikv/pd/pkg/mcs/utils/constant"
+	"github.com/tikv/pd/pkg/member"
 	"github.com/tikv/pd/pkg/storage/endpoint"
+	"github.com/tikv/pd/pkg/storage/kv"
 	"github.com/tikv/pd/pkg/utils/etcdutil"
 	"github.com/tikv/pd/pkg/utils/keypath"
 	"github.com/tikv/pd/pkg/utils/syncutil"
@@ -43,6 +45,7 @@ import (
 	"github.com/tikv/pd/pkg/utils/typeutil"
 	"go.etcd.io/etcd/api/v3/mvccpb"
 	clientv3 "go.etcd.io/etcd/client/v3"
+	"go.etcd.io/etcd/server/v3/embed"
 	"go.uber.org/goleak"
 )
 
@@ -59,6 +62,7 @@ type keyspaceGroupManagerTestSuite struct {
 	etcdClient       *clientv3.Client
 	clean            func()
 	cfg              *TestServiceConfig
+	servers          []*embed.Etcd
 }
 
 func TestKeyspaceGroupManagerTestSuite(t *testing.T) {
@@ -69,8 +73,8 @@ func (suite *keyspaceGroupManagerTestSuite) SetupSuite() {
 	t := suite.T()
 	suite.ctx, suite.cancel = context.WithCancel(context.Background())
 	suite.ClusterID = rand.Uint64()
-	servers, client, clean := etcdutil.NewTestEtcdCluster(t, 1)
-	suite.backendEndpoints, suite.etcdClient, suite.clean = servers[0].Config().ListenClientUrls[0].String(), client, clean
+	suite.servers, suite.etcdClient, suite.clean = etcdutil.NewTestEtcdCluster(t, 1)
+	suite.backendEndpoints = suite.servers[0].Config().ListenClientUrls[0].String()
 	suite.cfg = suite.createConfig()
 }
 
@@ -1215,3 +1219,46 @@ func waitForPrimariesServing(
 		return true
 	}, testutil.WithWaitFor(10*time.Second), testutil.WithTickInterval(50*time.Millisecond))
 }
+
+func (suite *keyspaceGroupManagerTestSuite) TestRegisterAllocatorConflict() {
+	re := suite.Require()
+
+	kgm := suite.newKeyspaceGroupManager(0, suite.ClusterID, suite.cfg)
+	re.NotNil(kgm)
+	defer kgm.Close()
+	kgm.Initialize()
+	participant, err := kgm.GetElectionMember(0, 0)
+	re.NoError(err)
+
+	legacySvcRootPath := keypath.LegacyRootPath(suite.ClusterID)
+	allocatorKeyPrefix := keypath.GlobalTSOAllocatorsPrefix(suite.ClusterID)
+	legacySvcStorage := endpoint.NewStorageEndpoint(kv.NewEtcdKVBase(suite.etcdClient, legacySvcRootPath), nil)
+	member := member.NewMember(suite.servers[0], suite.etcdClient, uint64(suite.servers[0].Server.ID()))
+	am := NewAllocatorManager(suite.ctx, suite.etcdClient, constant.DefaultKeyspaceGroupID, member, legacySvcRootPath, legacySvcStorage, kgm.cfg, allocatorKeyPrefix, path.Join(allocatorKeyPrefix, "pd"))
+	gta := NewGlobalTSOAllocator(suite.ctx, am)
+	err = gta.Initialize(0)
+	re.NoError(err)
+
+	kam := NewAllocatorManager(kgm.ctx, kgm.etcdClient, constant.DefaultKeyspaceGroupID, participant, kgm.legacySvcRootPath, kgm.legacySvcStorage, kgm.cfg, allocatorKeyPrefix, path.Join(allocatorKeyPrefix, "tso", fmt.Sprintf("keyspace_group_%d", constant.DefaultKeyspaceGroupID)))
+	kgta := NewGlobalTSOAllocator(suite.ctx, kam)
+	var wg sync.WaitGroup
+	wg.Add(1)
+	go func() {
+		defer wg.Done()
+		err = kgta.Initialize(0)
+		re.NoError(err)
+	}()
+
+	gta.Reset()
+	wg.Wait()
+
+	var wg1 sync.WaitGroup
+	wg1.Add(1)
+	go func() {
+		defer wg1.Done()
+		err = gta.Initialize(0)
+		re.NoError(err)
+	}()
+	kgta.Reset()
+	wg1.Wait()
+}