Try using foreground tasks for reliability

android/app/src/main/AndroidManifest.xml

@@ -61,6 +61,13 @@
             android:enabled="true"
             android:exported="true"
             android:permission="android.permission.INTERACT_ACROSS_USERS_FULL" />
+        <service 
+            android:name="com.pravera.flutter_foreground_task.service.ForegroundService"
+            android:foregroundServiceType="specialUse"
+            android:exported="false" />
+        <meta-data
+            android:name="dev.imranr.obtainium.service.NOTIFICATION_ICON"
+            android:resource="@drawable/ic_notification" />
     </application>
     <uses-permission android:name="android.permission.INTERNET" />
     <uses-permission android:name="android.permission.REQUEST_INSTALL_PACKAGES" />
@@ -74,6 +81,8 @@
         android:name="android.permission.WRITE_EXTERNAL_STORAGE"
         android:maxSdkVersion="29" />
     <uses-permission android:name="android.permission.QUERY_ALL_PACKAGES" />
+    <uses-permission android:name="android.permission.FOREGROUND_SERVICE" />
+    <uses-permission android:name="android.permission.FOREGROUND_SERVICE_SPECIAL_USE" />
     <!-- Required to query activities that can process text, see:
          https://developer.android.com/training/package-visibility and
          https://developer.android.com/reference/android/content/Intent#ACTION_PROCESS_TEXT.