The following PlatformException was thrown while de-activating platform stream on channel

[locskot]

flutter: ══╡ EXCEPTION CAUGHT BY SERVICES LIBRARY ╞══════════════════════════════════════════════════════════
flutter: The following PlatformException was thrown while de-activating platform stream on channel
flutter: cindyu.com/all_sensors/proximity:
flutter: PlatformException(error, No active stream to cancel, null, null)
flutter:
flutter: When the exception was thrown, this was the stack:
flutter: #0 StandardMethodCodec.decodeEnvelope (package:flutter/src/services/message_codecs.dart:581:7)
flutter: #1 MethodChannel._invokeMethod (package:flutter/src/services/platform_channel.dart:158:18)
flutter:
flutter: #2 EventChannel.receiveBroadcastStream. (package:flutter/src/services/platform_channel.dart:557:9)
flutter:
flutter: ════════════════════════════════════════════════════════════════════════════════════════════════════

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[locskot]

The problem was with two subscriptions which go almost simultaneously. So I did the following changes in the top of the widget tree:

final proximitySubject = PublishSubject();
proximitySubscription.clear();
proximitySubscription.add(proximityEvents.listen(proximitySubject.add));

and then observe the proximitySubject wherever I need proximityEvents;