[Huawei Watch] LSS4181:
Even after getting Android Wear 2.0 I'm still having this issue. At times (not every time) when I walk out of the phone's range and after I get back, the bluetooth pairing would be lost and I get the pairing request prompts on both the phone and the watch.

This issue is also being discussed in the Google forums as well, and is still ongoing.

It's not a big issue since completing the pairing will make it continue to function for the time being, but it can be annoying as if I'm not immediately aware of the problem the phone will keep making notification noises.

From the phone's logcat during the period I'm seeing something that makes me curious (The watch's Bluetooth device name and address have been obscured in the logs below since they're device-specific):

...

11-14 08:39:23.693 22071 22367 I WearableConn: Connecting to "HUAWEI WATCH XXXX"
11-14 08:39:23.696 22071 22367 W BluetoothAdapter: getBluetoothService() called with no BluetoothManagerCallback
11-14 08:39:24.245 318 5597 I NuPlayerDecoder: [audio] saw output EOS
11-14 08:39:24.636 318 5591 D NuPlayerDriver: notifyListener_l(0xf5f109c0), (2, 0, 0), loop setting(0, 0)
11-14 08:39:24.638 627 17971 I MediaFocusControl: AudioFocus abandonAudioFocus() from uid/pid 10034/820 clientId=android.media.AudioManager@db99f08
11-14 08:39:24.639 1193 1193 D AudioManager: AudioManager dispatching onAudioFocusChange(1) for android.media.AudioManager@1e92247<native proxy object>
11-14 08:39:25.398 4077 5602 I BistoWorker: XX:XX:XX:XX:XX:XX not paired anymore
11-14 08:39:25.727 4077 5602 I BistoWorker: isAvailable false
11-14 08:39:25.755 627 17970 I ActivityManager: Start proc 5603:com.google.android.googlequicksearchbox:interactor/u0a116 for service com.google.android.googlequicksearchbox/com.google.android.apps.gsa.staticplugins.bisto.BistoRealService
11-14 08:39:25.997 5603 5603 W AppFlowTracker: Removing 2 events from non-search process(com.google.android.googlequicksearchbox:interactor)
11-14 08:39:25.997 5603 5603 I InteractorInitializer: Initialized process com.google.android.googlequicksearchbox:interactor
11-14 08:39:26.275 5603 5603 D BluetoothA2dp: Proxy object connected
11-14 08:39:26.822 4077 4077 W SearchService: Abort, client detached.
11-14 08:39:26.823 4077 4077 I BistoWorker: handleCommonBroadcastIntent: android.bluetooth.device.action.ACL_CONNECTED
11-14 08:39:26.833 4077 4077 I DeviceDetector: Refreshing UUID cache for device: XX:XX:XX:XX:XX:XX
11-14 08:39:26.839 4077 4077 I BistoWorker: Not a bisto device: XX:XX:XX:XX:XX:XX
11-14 08:39:27.670 30272 30272 D WeatherUpdateService: onCreate
11-14 08:39:27.671 30272 30272 D WeatherUpdateService: Service started, but shouldn't update ... stopping
11-14 08:39:27.673 30272 30272 D WeatherUpdateService: onDestroy
11-14 08:39:27.837 820 820 D PhoneStatusBar: disable: < expand ICONS alerts SYSTEM_INFO back HOME RECENT clock SEARCH quick_settings >
11-14 08:39:27.848 820 820 W FingerprintManager: isFingerprintHardwareDetected(): Service not connected!
11-14 08:39:27.912 4077 4077 I BistoWorker: handleCommonBroadcastIntent: android.bluetooth.device.action.ACL_DISCONNECTED
11-14 08:39:27.917 4077 4077 I BistoWorker: Not a bisto device: XX:XX:XX:XX:XX:XX

...

11-14 08:39:32.846 820 1157 D CachedBluetoothDevice: onUuidChanged, mProfile Size 1
11-14 08:39:32.860 820 1157 D LocalBluetoothProfileManager: Current Profiles[HEADSET]
11-14 08:39:32.860 820 1157 D BluetoothMap: getConnectedDevices()
11-14 08:39:32.864 820 1157 D BluetoothMap: getConnectionState(XX:XX:XX:XX:XX:XX)
11-14 08:39:32.869 820 1157 D MapProfile: getConnectionStatus: status is: 0
11-14 08:39:32.871 820 1157 D LocalBluetoothProfileManager: New Profiles[HEADSET]
11-14 08:39:32.871 820 1157 D CachedBluetoothDevice: UUID not udpated, returning
11-14 08:39:32.955 4077 5602 I BistoWorker: XX:XX:XX:XX:XX:XX not paired anymore
11-14 08:39:32.957 4077 5602 I BistoWorker: isAvailable false
11-14 08:39:32.967 5603 5603 D BluetoothA2dp: Proxy object connected
11-14 08:39:33.617 627 1666 I ActivityManager: START u0 {act=android.bluetooth.device.action.PAIRING_REQUEST flg=0x10000000 cmp=com.android.settings/.bluetooth.BluetoothPairingDialog (has extras)} from uid 1000 on display 0
11-14 08:39:33.630 627 4446 W InputMethodManagerService: Window already focused, ignoring focus gain of: com.android.internal.view.IInputMethodClient$Stub$Proxy@9595304 attribute=null, token = android.os.BinderProxy@54c2870
11-14 08:39:33.660 302 366 I chatty : uid=1000(system) UeventObserver expire 48 lines
11-14 08:39:33.723 627 967 E ActivityManager: applyOptionsLocked: Unknown animationType=0
11-14 08:39:33.724 1681 1761 D StreamDBQueue: Promised revision #698657 to queue a new op
11-14 08:39:33.724 1681 1761 D BaseStreamManager: Promised remove @ r#698657 for StreamItemId{notifKey=0|com.android.settings|17301632|null|1000, packageName=com.android.settings, id=17301632, revision=-1, originalRevision=-1, updateCount=-1} (@698656): SBN removed: StreamItemId{notifKey=0|com.android.settings|17301632|null|1000, packageName=com.android.settings, id=17301632, revision=-1, originalRevision=-1, updateCount=-1}
11-14 08:39:33.725 1681 1804 D NewStreamAdapter: Publishing revision #698657 to adapter clients
11-14 08:39:33.727 1681 1761 D StreamDBQueue: Promised revision #698658 to queue a new op
11-14 08:39:33.727 1681 1761 D BaseStreamManager: Promised remove @ r#698658 for StreamItemId{notifKey=-1|android|17040570|null|1000, packageName=android, id=17040570, revision=-1, originalRevision=-1, updateCount=-1} (@698657): SBN removed: StreamItemId{notifKey=-1|android|17040570|null|1000, packageName=android, id=17040570, revision=-1, originalRevision=-1, updateCount=-1}
11-14 08:39:33.728 1681 1804 D NewStreamAdapter: Publishing revision #698658 to adapter clients
11-14 08:39:33.729 810 810 W InputMethodService: Window size has been changed. This may cause jankiness of resizing window: -1 -> -2
11-14 08:39:33.976 302 302 I chatty : uid=1000(system) /system/bin/surfaceflinger expire 47 lines
11-14 08:39:34.017 4077 4077 W SearchService: Abort, client detached.
11-14 08:39:34.017 4077 4077 I BistoWorker: handleCommonBroadcastIntent: android.bluetooth.device.action.ACL_CONNECTED
11-14 08:39:34.020 4077 4077 E DeviceDetector: UUID = 0000110a-0000-1000-8000-00805f9b34fb
11-14 08:39:34.020 4077 4077 E DeviceDetector: UUID = 0000111e-0000-1000-8000-00805f9b34fb
11-14 08:39:34.021 4077 4077 E DeviceDetector: UUID = 00000000-0000-1000-8000-00805f9b34fb
11-14 08:39:34.021 4077 4077 E DeviceDetector: UUID = 669a0c20-0008-e2a5-e311-2595b045895e
11-14 08:39:34.021 4077 4077 I BistoWorker: Not a bisto device: XX:XX:XX:XX:XX:XX
11-14 08:39:34.033 627 4441 I ActivityManager: Setting hasTopUi=false for pid=820
11-14 08:39:34.034 820 820 D PhoneStatusBar: disable: < expand icons* alerts system_info* back home recent clock search quick_settings >
11-14 08:39:34.249 5572 5667 I OpenGLRenderer: Initialized EGL, version 1.4
11-14 08:39:34.249 5572 5667 D OpenGLRenderer: Swap behavior 1
11-14 08:39:34.251 5572 5667 W OpenGLRenderer: Failed to choose config with EGL_SWAP_BEHAVIOR_PRESERVED, retrying without...
11-14 08:39:34.251 5572 5667 D OpenGLRenderer: Swap behavior 0
11-14 08:39:34.483 627 649 I ActivityManager: Displayed com.android.settings/.bluetooth.BluetoothPairingDialog: +760ms
11-14 08:39:35.078 4077 4077 W SearchService: Abort, client detached.
11-14 08:39:35.079 4077 4077 I BistoWorker: handleCommonBroadcastIntent: android.bluetooth.device.action.ACL_DISCONNECTED
11-14 08:39:35.086 4077 4077 E DeviceDetector: UUID = 0000110a-0000-1000-8000-00805f9b34fb
11-14 08:39:35.087 4077 4077 E DeviceDetector: UUID = 0000111e-0000-1000-8000-00805f9b34fb
11-14 08:39:35.088 4077 4077 E DeviceDetector: UUID = 00000000-0000-1000-8000-00805f9b34fb
11-14 08:39:35.088 4077 4077 E DeviceDetector: UUID = 669a0c20-0008-e2a5-e311-2595b045895e
11-14 08:39:35.089 4077 4077 I BistoWorker: Not a bisto device: XX:XX:XX:XX:XX:XX
11-14 08:39:35.285 16265 16295 I chatty : uid=1002(bluetooth) bt_workqueue expire 10 lines
11-14 08:39:35.286 16265 16292 I chatty : uid=1002(bluetooth) hci_thread expire 35 lines
11-14 08:39:35.330 16265 16295 I chatty : uid=1002(bluetooth) bt_workqueue expire 14 lines
11-14 08:39:35.891 5572 5572 I BluetoothPairingDialog: Pairing dialog accepted
11-14 08:39:35.920 627 9114 W InputMethodManagerService: Window already focused, ignoring focus gain of: com.android.internal.view.IInputMethodClient$Stub$Proxy@854061b attribute=null, token = android.os.BinderProxy@54c2870
11-14 08:39:35.986 5572 5667 D OpenGLRenderer: endAllActiveAnimators on 0xf176a080 (RippleDrawable) with handle 0xf14f5ac0
11-14 08:39:38.985 308 390 I chatty : uid=1041(audioserver) /system/bin/audioserver expire 53 lines
11-14 08:39:40.126 4077 5602 I BistoWorker: XX:XX:XX:XX:XX:XX not paired anymore
11-14 08:39:40.130 4077 5602 I BistoWorker: isAvailable false
11-14 08:39:40.160 5603 5603 D BluetoothA2dp: Proxy object connected
11-14 08:39:41.250 4077 4077 W SearchService: Abort, client detached.

...

It appears either the phone (Android Wear) or the watch unpaired in the background, in a one-sided manner, so that the log on the phone reported that the device is "not paired anymore".