RxAndroidBle: stuck on connecting on Huawei device trying to connect to BLE device

im trying to connect to different BLE devices from a Huawei P9 lite but it gets stuck in connecting state in most of the times. if i clear bluetooth share system application’s cache, connection will be successful for the first time sometimes but it will again get stuck to connecting state after trying to reconnect.

steps to reproduce: 1- try to connect to a ble device from Huawei P9 lite (its probably unsuccessful in first try but if its not go on) 2- turn off BLE device or turn off mobile bluetooth 3- try to reconnect and it gets stuck in connecting and nothing else happens.

my code snippet is:

                  rxBleClient

                    .scanBleDevices(getSettings(), getFilter())

                    .timeout(SCAN_TIMEOUT, TimeUnit.MILLISECONDS, Observable.empty())

                    .observeOn(AndroidSchedulers.mainThread())

                    .subscribeBy(
                            onNext = { scanResult ->
                                device = scanResult.bleDevice
                                Timber.i("Found $device")
                            },
                            onError = { throwable ->
                                Timber.e(throwable)
                            },
                            onComplete = {
                                device?.let {
                                    startConnecting(it)
                                }
                                        ?: Toast.makeText(context, "No device found!", Toast.LENGTH_LONG).show()
                            })

start connecting method:

   private fun startConnecting(device: RxBleDevice) {
    Timber.i("connecting to $device")

    mayDisconnect()

    connectionStateDisposable = device.observeConnectionStateChanges()
            .observeOn(AndroidSchedulers.mainThread())
            .subscribeBy(
                    onNext = { connectionState: RxBleConnection.RxBleConnectionState ->
                        when (connectionState) {
                            RxBleConnection.RxBleConnectionState.CONNECTING -> Timber.i("connecting...")
                            RxBleConnection.RxBleConnectionState.CONNECTED -> Timber.i("connected!")
                            RxBleConnection.RxBleConnectionState.DISCONNECTING -> Timber.i("disconnecting...")
                            RxBleConnection.RxBleConnectionState.DISCONNECTED -> Timber.i("disconnected!!!")
                        }
                    },
                    onError = { throwable ->
                        Timber.w(throwable)
                    },
                    onComplete = {
                        Timber.i("state change complete!")
                    })

    connectionDisposable = device.establishConnection(true)
            .subscribeBy(
                    onNext = { bleConnection ->
                        this@MainActivity.bleConnection = bleConnection
                        requestMTU()
                        readCounter()
                        registerCounter()
                    },
                    onError = { throwable ->
                        Timber.e(throwable, "Device disconnected: ${device.name}(${device.macAddress})")
                    },
                    onComplete = {
                        Timber.i("connection complete!")
                    })
}

the log is:

 I/RxBle#QueueOperation: Scan operation is requested to start.
 I/BluetoothAdapter: getBluetoothLeScanner
 I/MainActivity$startScan(MainActivity.kt:152): Found RxBleDeviceImpl{bluetoothDevice=Things(62:B2:C6:E2:00:6E)}
 I/RxBle#CancellableDisposable: Scan operation is requested to stop.
 I/BluetoothAdapter: getBluetoothLeScanner
 I/MainActivity(MainActivity.kt:183): connecting to RxBleDeviceImpl{bluetoothDevice=Things(62:B2:C6:E2:00:6E)}
 I/MainActivity$startConnecting(MainActivity.kt:192): connecting...

expected: it should connect after finding the device and calling establishConnection method.

actual: it gets stuck in connecting state

android app repo: https://github.com/mohsenoid/android-things-ble-sample-app

android things gat repo: https://github.com/mohsenoid/android-things-ble-sample