NoSuchElementException when calling discoverAllServices

[milgner]

Describe the bug
When I try to discover the services on a BLE device by calling flutterReactiveBl.discoverAllServices, I sometimes get an exception:

PlatformException: service_discovery_failure
Caused by: java.util.NoSuchElementException

  # RxJava
  at io.reactivex.internal.operators.observable.ObservableElementAtSingle$ElementAtObserver.onComplete(ObservableElementAtSingle.java:115)
  at io.reactivex.internal.operators.observable.ObservableFlatMapSingle$FlatMapSingleObserver.drainLoop(ObservableFlatMapSingle.java:254)
  at io.reactivex.internal.operators.observable.ObservableFlatMapSingle$FlatMapSingleObserver.drain(ObservableFlatMapSingle.java:210)
  at io.reactivex.internal.operators.observable.ObservableFlatMapSingle$FlatMapSingleObserver.onComplete(ObservableFlatMapSingle.java:133)
  at io.reactivex.subjects.BehaviorSubject.subscribeActual(BehaviorSubject.java:244)
  at io.reactivex.Observable.subscribe(Observable.java:12284)
  at io.reactivex.internal.operators.observable.ObservableFlatMapSingle.subscribeActual(ObservableFlatMapSingle.java:48)
  at io.reactivex.Observable.subscribe(Observable.java:12284)
  at io.reactivex.internal.operators.observable.ObservableElementAtSingle.subscribeActual(ObservableElementAtSingle.java:37)
  at io.reactivex.Single.subscribe(Single.java:3666)
  at io.reactivex.internal.operators.single.SingleObserveOn.subscribeActual(SingleObserveOn.java:35)
  at io.reactivex.Single.subscribe(Single.java:3666)
  at io.reactivex.Single.subscribe(Single.java:3652)

  # flutter_reactive_ble
  at com.signify.hue.flutterreactiveble.PluginController.discoverServices(PluginController.kt:366)
  at com.signify.hue.flutterreactiveble.PluginController.access$discoverServices(PluginController.kt:23)
  at com.signify.hue.flutterreactiveble.PluginController$pluginMethods$14.invoke(PluginController.kt:40)
  at com.signify.hue.flutterreactiveble.PluginController$pluginMethods$14.invoke(PluginController.kt:40)
  at com.signify.hue.flutterreactiveble.PluginController.execute$reactive_ble_mobile_debug(PluginController.kt:89)
  at com.signify.hue.flutterreactiveble.ReactiveBlePlugin.onMethodCall(ReactiveBlePlugin.kt:44)

  # Flutter
  at io.flutter.plugin.common.MethodChannel$IncomingMethodCallHandler.onMessage(MethodChannel.java:267)
  at io.flutter.embedding.engine.dart.DartMessenger.invokeHandler(DartMessenger.java:286)
  at io.flutter.embedding.engine.dart.DartMessenger.lambda$dispatchMessageToQueue$0$io-flutter-embedding-engine-dart-DartMessenger(DartMessenger.java:313)
  at io.flutter.embedding.engine.dart.DartMessenger$$ExternalSyntheticLambda0.run(D8$$SyntheticClass:0)

  # Android
  at android.os.Handler.handleCallback(Handler.java:995)
  at android.os.Handler.dispatchMessage(Handler.java:103)
  at android.os.Looper.loopOnce(Looper.java:273)
  at android.os.Looper.loop(Looper.java:363)
  at android.app.ActivityThread.main(ActivityThread.java:10060)
  at java.lang.reflect.Method.invoke(Native Method)
  at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:632)
  at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:975)

To Reproduce
Steps to reproduce the behavior:

1. Run flutterRecativeBle.scanForDevices
2. Call flutterReactiveBle.discoverAllServices` with the ID of that device to connect to the GATT server and get a full service list instead only service information from BLE service announcements
3. Observe a failure with exception (including the part of the stack trace, belonging to this package) …

Expected behavior
Services are discovered and no exception is thrown.
I wrote a small Python script to check whether the device might be at fault but my Python script (using bleak) could both discover and connect the device, fetching the full service and characteristic list without any issues.

Smartphone / tablet

• Device: Samsung Galaxy S25
• OS: Android 16
• Package version: 5.4.0

Peripheral device

• Vendor, model: cosinuss c-med alpha
• Does it run a custom firmware / software: no