Impossible to sync or add device vivoactive HR

Hi there,
Not sure if this will help but here goes. I have been fighting all weekend with a Vivosport and a Huawei P9 lite. Bought the vivosport for my girls birthday and was all set to return it tomorrow due to the disconnect/can't connect issues.
Anyway i have found (so far) a reasonable work around until they hopefully get an update out.
The connection hasn't dropped all day, i can switch off blue tooth on the phone and then then switch it back on and reconnect without any problems - so far :)
I basically went looking for an older version of the Garmin app here (https://www.apkmonk.com/app/com.garmin.android.apps.connectmobile/) and i tried a few different ones from last year and finally settled on v. 3.16 from last march.
So you will need to:
- uninstall the existing garmin connect app
- set your app updates in google store to manual - not automatic over wifi otherwise you will auto update garmin connect and have the same problem again
- download an APK installer - i used App Manager
- download Play Services Info app - we will need this later
- download the older APK file to your phone and install it through the APK installer app
- uninstall google services updates - you do this from your app list (other people were noting that this was causing a problem with the initial pairing so i went ahead and uninstalled them) - don't worry we will be reinstalling the updates later.
Now as you have uninstalled the previous version of garmin connect you will need to pair your phone and device again. I seemed to have the most luck with pairing it directly via the blue tooth settings in my phone and putting in the number which appears on the watch/fit band screen WHILST having garmin connect closed.
Initially the phone showed it as being connected but the garmin connect did not but when i went to "add device" in garmin connect and ran the "pair now" from the watch/fit band screen it connected and loaded up in around 30 secs.

So now we are all connected and everything is working but if you don't update the google play services you will have google problems.
So now we run Play Services Info and that will download the uninstalled updates and reset google play services back to normal.

I originally tried an apk from october 2017 and that appeared to work fine however as soon as i switched off gps the connection would drop and i could not reconnect. Some people have already talked about the location services needing to be switched on and off to get the connection and even then it can still fail.

Just to repeat this is with a Huawei P9 lite and the new Garmin vivosport (2017) connection has been stable for over 10 hrs now and we can disconnect and reconnect at will.
You are stuck with the older interface on your phone but until somebody sorts out the update hopefully this will solve some problems.

Good luck and if you have any questions please fire away ;)

I've had something similar with my vivoactive 3 and my HTC U11. I eventually fixed it by deleting the paired vivoactive 3 in my phone's bluetooth settings. I rebooted my phone and then tried to pair my watch to my phone. For me that worked. I hope it works for you too.