diff --git a/src/com/android/settings/applications/specialaccess/notificationaccess/NotificationAccessDetails.java b/src/com/android/settings/applications/specialaccess/notificationaccess/NotificationAccessDetails.java
index 6a4c22e..c77c2b9 100644
--- a/src/com/android/settings/applications/specialaccess/notificationaccess/NotificationAccessDetails.java
+++ b/src/com/android/settings/applications/specialaccess/notificationaccess/NotificationAccessDetails.java
@@ -181,7 +181,10 @@
 
     public void updatePreference(SwitchPreference preference) {
         final CharSequence label = mPackageInfo.applicationInfo.loadLabel(mPm);
+        final boolean isAllowedCn = mComponentName.flattenToShortString().length()
+                <= NotificationManager.MAX_SERVICE_COMPONENT_NAME_LENGTH;
         preference.setChecked(isServiceEnabled(mComponentName));
+        preference.setEnabled(preference.isChecked() || isAllowedCn);
         preference.setOnPreferenceChangeListener((p, newValue) -> {
             final boolean access = (Boolean) newValue;
             if (!access) {
diff --git a/src/com/android/settings/notification/NotificationAccessConfirmationActivity.java b/src/com/android/settings/notification/NotificationAccessConfirmationActivity.java
index dfe6df2..a6b565a 100644
--- a/src/com/android/settings/notification/NotificationAccessConfirmationActivity.java
+++ b/src/com/android/settings/notification/NotificationAccessConfirmationActivity.java
@@ -67,7 +67,9 @@
         mUserId = getIntent().getIntExtra(EXTRA_USER_ID, UserHandle.USER_NULL);
         CharSequence mAppLabel;
 
-        if (mComponentName == null || mComponentName.getPackageName() == null) {
+        if (mComponentName == null || mComponentName.getPackageName() == null
+                || mComponentName.flattenToString().length()
+                > NotificationManager.MAX_SERVICE_COMPONENT_NAME_LENGTH) {
             finish();
             return;
         }
diff --git a/src/com/android/settings/notification/NotificationAccessSettings.java b/src/com/android/settings/notification/NotificationAccessSettings.java
index 79e75bd..20e019e 100644
--- a/src/com/android/settings/notification/NotificationAccessSettings.java
+++ b/src/com/android/settings/notification/NotificationAccessSettings.java
@@ -58,8 +58,6 @@
 public class NotificationAccessSettings extends EmptyTextSettings {
     private static final String TAG = "NotifAccessSettings";
 
-    private static final int MAX_CN_LENGTH = 500;
-
     private static final ManagedServiceSettings.Config CONFIG =
             new ManagedServiceSettings.Config.Builder()
                     .setTag(TAG)
@@ -135,7 +133,8 @@
         for (ServiceInfo service : services) {
             final ComponentName cn = new ComponentName(service.packageName, service.name);
             boolean isAllowed = mNm.isNotificationListenerAccessGranted(cn);
-            if (!isAllowed && cn.flattenToString().length() > MAX_CN_LENGTH) {
+            if (!isAllowed && cn.flattenToString().length()
+                    > NotificationManager.MAX_SERVICE_COMPONENT_NAME_LENGTH) {
                 continue;
             }