diff --git a/src/link_manager/LinkManagerStateMachineActiveActive.cpp b/src/link_manager/LinkManagerStateMachineActiveActive.cpp
index fc7e10c..47e8dd6 100644
--- a/src/link_manager/LinkManagerStateMachineActiveActive.cpp
+++ b/src/link_manager/LinkManagerStateMachineActiveActive.cpp
@@ -780,7 +780,7 @@ void ActiveActiveStateMachine::LinkProberActiveMuxStandbyLinkUpTransitionFunctio
             // last siwtch mux state to standby failed, try again
             switchMuxState(nextState, mux_state::MuxState::Label::Standby, true);
         }
-    } else {
+    } else if (mDefaultRouteState != DefaultRoute::NA) {
         switchMuxState(nextState, mux_state::MuxState::Label::Active);
     }
 }
diff --git a/test/LinkManagerStateMachineActiveActiveTest.cpp b/test/LinkManagerStateMachineActiveActiveTest.cpp
index 683206d..62303e9 100644
--- a/test/LinkManagerStateMachineActiveActiveTest.cpp
+++ b/test/LinkManagerStateMachineActiveActiveTest.cpp
@@ -500,6 +500,35 @@ TEST_F(LinkManagerStateMachineActiveActiveTest, MuxActivDefaultRouteState)
     EXPECT_EQ(mFakeMuxPort.mFakeLinkProber->mRestartTxProbeCallCount, 3);
 }
 
+TEST_F(LinkManagerStateMachineActiveActiveTest, MuxActivDefaultRouteStateNALMuxProbeActiveAfterToggle)
+{
+    setMuxActive();
+
+    mMuxConfig.enableDefaultRouteFeature(true);
+    postDefaultRouteEvent("na", 1);
+    EXPECT_EQ(mFakeMuxPort.mFakeLinkProber->mShutdownTxProbeCallCount, 1);
+    EXPECT_EQ(mFakeMuxPort.mFakeLinkProber->mRestartTxProbeCallCount, 0);
+    EXPECT_EQ(mDbInterfacePtr->mSetMuxStateInvokeCount, 2);
+    EXPECT_EQ(mDbInterfacePtr->mLastSetMuxState, mux_state::MuxState::Label::Standby);
+    VALIDATE_STATE(Active, Standby, Up);
+
+    // misleading mux state active from periodically probe
+    handleProbeMuxState("active", 3);
+    EXPECT_EQ(mDbInterfacePtr->mSetMuxStateInvokeCount, 2);
+    EXPECT_EQ(mDbInterfacePtr->mLastSetMuxState, mux_state::MuxState::Label::Standby);
+    VALIDATE_STATE(Active, Active, Up);
+
+    handleMuxState("standby", 3);
+    EXPECT_EQ(mDbInterfacePtr->mSetMuxStateInvokeCount, 2);
+    EXPECT_EQ(mDbInterfacePtr->mLastSetMuxState, mux_state::MuxState::Label::Standby);
+    VALIDATE_STATE(Active, Standby, Up);
+
+    postLinkProberEvent(link_prober::LinkProberState::Unknown, 3);
+    EXPECT_EQ(mDbInterfacePtr->mSetMuxStateInvokeCount, 2);
+    EXPECT_EQ(mDbInterfacePtr->mLastSetMuxState, mux_state::MuxState::Label::Standby);
+    VALIDATE_STATE(Unknown, Standby, Up);
+}
+
 TEST_F(LinkManagerStateMachineActiveActiveTest, MuxActivDefaultRouteStateMuxConfigActive)
 {
     setMuxActive();