diff --git a/enforcer.go b/enforcer.go
index 3914cc8..f26fb44 100644
--- a/enforcer.go
+++ b/enforcer.go
@@ -214,7 +214,7 @@ func (e *Enforcer) LoginByModel(id string, loginModel *model.Login, ctx ctx.Cont
 	if session = e.GetSession(id); session == nil {
 		session = model.NewSession("0", "account-session", id)
 	}
-	session.AddTokenSign(&model.TokenSign{
+	session.AddDistinctValueTokenSign(&model.TokenSign{
 		Value:  tokenValue,
 		Device: device,
 	})
diff --git a/enforcer_test.go b/enforcer_test.go
index 453cf1d..3428974 100644
--- a/enforcer_test.go
+++ b/enforcer_test.go
@@ -440,11 +440,11 @@ func TestEnforcer_JsonAdapter(t *testing.T) {
 		t.Fatalf("NewEnforcer() failed: %v", err)
 	}
 	newSession := model.NewSession("1", "2", "3")
-	newSession.AddTokenSign(&model.TokenSign{
+	newSession.AddDistinctValueTokenSign(&model.TokenSign{
 		Value:  "2",
 		Device: "device",
 	})
-	newSession.AddTokenSign(&model.TokenSign{
+	newSession.AddDistinctValueTokenSign(&model.TokenSign{
 		Value:  "3",
 		Device: "device",
 	})
diff --git a/model/session.go b/model/session.go
index 6480133..5f47459 100644
--- a/model/session.go
+++ b/model/session.go
@@ -93,6 +93,11 @@ func (s *Session) GetTokenSign(tokenValue string) *TokenSign {
 
 // AddTokenSign add TokenSign
 func (s *Session) AddTokenSign(sign *TokenSign) {
+	s.TokenSignList = append(s.TokenSignList, sign)
+}
+
+// AddDistinctValueTokenSign check tokenValue ,then add TokenSign
+func (s *Session) AddDistinctValueTokenSign(sign *TokenSign) {
 	if s.GetTokenSign(sign.Value) != nil {
 		return
 	}