diff --git a/src/com/android/services/telephony/TelephonyConnectionService.java b/src/com/android/services/telephony/TelephonyConnectionService.java
index a510e51..2abf1e2 100644
--- a/src/com/android/services/telephony/TelephonyConnectionService.java
+++ b/src/com/android/services/telephony/TelephonyConnectionService.java
@@ -2303,11 +2303,15 @@
                     // On GSM phones, null connection means that we dialed an MMI code
                     int telephonyDisconnectCause = handleMmiCode(
                             phone, android.telephony.DisconnectCause.OUTGOING_FAILURE);
-                    mNormalCallConnection.setTelephonyConnectionDisconnected(mDisconnectCauseFactory
-                            .toTelecomDisconnectCause(telephonyDisconnectCause,
-                                    "Connection is null", phone.getPhoneId()));
+                    if (mNormalCallConnection.getState() != Connection.STATE_DISCONNECTED) {
+                        mNormalCallConnection.setTelephonyConnectionDisconnected(
+                                mDisconnectCauseFactory.toTelecomDisconnectCause(
+                                        telephonyDisconnectCause,
+                                        "Connection is null",
+                                        phone.getPhoneId()));
+                        mNormalCallConnection.close();
+                    }
                     clearNormalCallDomainSelectionConnection();
-                    mNormalCallConnection.close();
                     return;
                 }
 
@@ -2354,6 +2358,7 @@
         boolean isMmiCode = (dialPart.startsWith("*") || dialPart.startsWith("#"))
                 && dialPart.endsWith("#");
         boolean isSuppServiceCode = ImsPhoneMmiCode.isSuppServiceCodes(dialPart, phone);
+        boolean isPotentialUssdCode = isMmiCode && !isSuppServiceCode;
 
         // If the number is both an MMI code and a supplementary service code,
         // it shall be treated as UT. In this case, domain selection is not performed.
@@ -2362,6 +2367,10 @@
             return false;
         }
 
+        /* For USSD codes, connection is closed and MMIDialogActivity is started.
+           To avoid connection close and return false. isPotentialUssdCode is handled after
+            all condition checks. */
+
         // Check and select same domain as ongoing call on the same subscription (if exists)
         int activeCallDomain = getActiveCallDomain(phone.getSubId());
         if (activeCallDomain != NetworkRegistrationInfo.DOMAIN_UNKNOWN
@@ -2397,6 +2406,15 @@
         mNormalCallConnection = connection;
         future.thenAcceptAsync((domain) -> handleOutgoingCallConnectionByCallDomainSelection(
                 domain, phone, number, videoState), mDomainSelectionMainExecutor);
+
+        if (isPotentialUssdCode) {
+            Log.v(LOG_TAG, "PotentialUssdCode. Closing connection with DisconnectCause.DIALED_MMI");
+            connection.setTelephonyConnectionDisconnected(
+                    mDisconnectCauseFactory.toTelecomDisconnectCause(
+                            android.telephony.DisconnectCause.DIALED_MMI,
+                            "Dialing USSD", phone.getPhoneId()));
+            connection.close();
+        }
         return true;
     }
 
diff --git a/src/com/android/services/telephony/domainselection/EmergencyCallDomainSelector.java b/src/com/android/services/telephony/domainselection/EmergencyCallDomainSelector.java
index 05ae1f0..b790e8a 100644
--- a/src/com/android/services/telephony/domainselection/EmergencyCallDomainSelector.java
+++ b/src/com/android/services/telephony/domainselection/EmergencyCallDomainSelector.java
@@ -657,6 +657,13 @@
     private void selectDomainFromInitialState() {
         if (mDestroyed) return;
 
+        if (isInEmergencyCallbackModeOnPsWwan()) {
+            logi("selectDomain PS cellular connected in ECBM");
+            mPsNetworkType = EUTRAN;
+            onWwanNetworkTypeSelected(mPsNetworkType);
+            return;
+        }
+
         boolean csInService = isCsInService();
         boolean psInService = isPsInService();
 
@@ -1604,6 +1611,12 @@
                 && mEcbmHelper.getDataConnectionState(getSlotId()) == DATA_CONNECTED;
     }
 
+    private boolean isInEmergencyCallbackModeOnPsWwan() {
+        return mEcbmHelper.isInEmergencyCallbackMode(getSlotId())
+                && mEcbmHelper.getTransportType(getSlotId()) == TRANSPORT_TYPE_WWAN
+                && mEcbmHelper.getDataConnectionState(getSlotId()) == DATA_CONNECTED;
+    }
+
     @Override
     protected void logi(String msg) {
         super.logi(msg);
diff --git a/src/com/android/services/telephony/domainselection/EmergencyCallbackModeHelper.java b/src/com/android/services/telephony/domainselection/EmergencyCallbackModeHelper.java
index e42dfe7..cdf2225 100644
--- a/src/com/android/services/telephony/domainselection/EmergencyCallbackModeHelper.java
+++ b/src/com/android/services/telephony/domainselection/EmergencyCallbackModeHelper.java
@@ -68,7 +68,7 @@
                 @NonNull PreciseDataConnectionState dataConnectionState) {
             ApnSetting apnSetting = dataConnectionState.getApnSetting();
             if ((apnSetting == null)
-                    || ((apnSetting.getApnTypeBitmask() | ApnSetting.TYPE_EMERGENCY) == 0)) {
+                    || ((apnSetting.getApnTypeBitmask() & ApnSetting.TYPE_EMERGENCY) == 0)) {
                 return;
             }
             mTransportType = dataConnectionState.getTransportType();
diff --git a/tests/src/com/android/services/telephony/domainselection/EmergencyCallDomainSelectorTest.java b/tests/src/com/android/services/telephony/domainselection/EmergencyCallDomainSelectorTest.java
index b8b3359..39f01a2 100644
--- a/tests/src/com/android/services/telephony/domainselection/EmergencyCallDomainSelectorTest.java
+++ b/tests/src/com/android/services/telephony/domainselection/EmergencyCallDomainSelectorTest.java
@@ -2877,6 +2877,16 @@
         doReturn(TRANSPORT_TYPE_WWAN).when(mEcbmHelper).getTransportType(anyInt());
         doReturn(DATA_CONNECTED).when(mEcbmHelper).getDataConnectionState(anyInt());
 
+        doAnswer(new Answer<Void>() {
+            @Override
+            public Void answer(InvocationOnMock invocation) throws Throwable {
+                Consumer<WwanSelectorCallback> consumer =
+                        (Consumer<WwanSelectorCallback>) invocation.getArguments()[0];
+                consumer.accept(mWwanSelectorCallback);
+                return null;
+            }
+        }).when(mTransportSelectorCallback).onWwanSelected(any());
+
         EmergencyRegistrationResult regResult = getEmergencyRegResult(UNKNOWN,
                 REGISTRATION_STATE_UNKNOWN,
                 0, false, false, 0, 0, "", "");
@@ -2889,6 +2899,7 @@
 
         verify(mTransportSelectorCallback, never()).onWlanSelected(anyBoolean());
         verify(mTransportSelectorCallback).onWwanSelected(any());
+        verify(mWwanSelectorCallback).onDomainSelected(eq(DOMAIN_PS), eq(true));
     }
 
     @Test
@@ -2959,6 +2970,42 @@
         verify(mTransportSelectorCallback).onWwanSelected(any());
     }
 
+    @Test
+    public void testNotInEcbmOnWwanConnected() throws Exception {
+        createSelector(SLOT_0_SUB_ID);
+        unsolBarringInfoChanged(false);
+
+        doReturn(false).when(mEcbmHelper).isInEmergencyCallbackMode(anyInt());
+        doReturn(TRANSPORT_TYPE_WLAN).when(mEcbmHelper).getTransportType(anyInt());
+        doReturn(DATA_CONNECTED).when(mEcbmHelper).getDataConnectionState(anyInt());
+
+        doAnswer(new Answer<Void>() {
+            @Override
+            public Void answer(InvocationOnMock invocation) throws Throwable {
+                Consumer<WwanSelectorCallback> consumer =
+                        (Consumer<WwanSelectorCallback>) invocation.getArguments()[0];
+                consumer.accept(mWwanSelectorCallback);
+                return null;
+            }
+        }).when(mTransportSelectorCallback).onWwanSelected(any());
+
+        EmergencyRegistrationResult regResult = getEmergencyRegResult(UNKNOWN,
+                REGISTRATION_STATE_UNKNOWN,
+                0, false, false, 0, 0, "", "");
+        SelectionAttributes attr = getSelectionAttributes(SLOT_0, SLOT_0_SUB_ID, regResult);
+        mDomainSelector.selectDomain(attr, mTransportSelectorCallback);
+        processAllMessages();
+
+        bindImsServiceUnregistered();
+        processAllMessages();
+
+        verify(mTransportSelectorCallback, never()).onWlanSelected(anyBoolean());
+        verify(mTransportSelectorCallback).onWwanSelected(any());
+        verify(mWwanSelectorCallback, never()).onDomainSelected(anyInt(), anyBoolean());
+        verify(mWwanSelectorCallback).onRequestEmergencyNetworkScan(
+                any(), anyInt(), anyBoolean(), any(), any());
+    }
+
     private void setupForScanListTest(PersistableBundle bundle) throws Exception {
         setupForScanListTest(bundle, false);
     }