vivoactive 5 10.20 - unstable connection and hung

I have the same problem.  My Vivoactive 5 updated to 10.20 and has several times asked to Bluetooth pair to my phone, a Pixel 8a.  My Garmin Connect app is version 5.1.  I concur, this was not a problem before.  

ETA:  The first time it did this after the update, I had to set  up the VA5 as new, reconnecting it to our Wifi and going through the setup.  This has not happened in subsequent pairing requests.  I also noticed on a walk yesterday it did not automatically start the activity.

Same problem here. 

Just bought the watch and updated it. 

Now it loses connection and wants to re pair every few minutes to hours... 

I did a reset of my watch yesterday early evening. This did not help. It was not connected to my phone all night. Can we roll back to the prior version?

I just chatted in with customer service and was told this:

it seems the updates didn't go through. Update through the watch – press the bottom button – settings – system – software update

When I initially got the update notification, it said it was about 3 minutes, I believe, and I was at the grocery store.  I just tried this at home, even though it said I was on version 10.20 on my watch, and went through the update process.  It found my Wifi, then did a 1 minute update.  Fingers crossed this fixes the problem!

ETA:  I did this yesterday afternoon and it's been completely solid since then.  No asking to reconnect whatsoever.

This didn't changed anything for me. 

According to the watch it's on the latest version. 

I tried resetting the watch and it took me like 10 retries to even get the watch connected to the phone. 

But then it just again in the connected, disconnected, re pair loop. 

I disabled the Bluetooth for now so the messages don't bother me like every minute... 

Mr.Pearce said:

his didn't changed anything for me. 

According to the watch it's on the latest version. 

I tried resetting the watch and it took me like 10 retries to even get the watch connected to the phone. 

But then it just again in the connected, disconnected, re pair loop. 

I disabled the Bluetooth for now so the messages don't bother me like every minute... 

I really hope I'm not stepping on toes here, but this sounds almost like a different thing.  When you say you are having the disconnect and reconnect thing happen often, is it "connected alerts?"  In other words, are you seeing your watch pop up a notification at the top that says, "phone disconnected" and "phone reconnected?" or are you seeing the string of numbers on your watch and phone to reconnect?

If it's the phone disconnected/phone reconnected messages, that's totally normal, happens when you walk away from your phone, and can be disabled.  (long press bottom button - settings - system - connectivity - phone - turn off connected alerts)

According to my watch it was on the latest version as well, but the steps I executed last night seem to have solved the problem for me. Disabling Bluetooth is a difficult solution because it prevents syncing from your phone and watch.  I highly recommend chatting in with customer service.  They solved my issue, and Garmin's CS is really good.  It's one of the reasons this is my second Garmin device.

I tried your process and the watch says there is no update. 

The watch disconnects and connects like every few minutes even when the phone is in my pocket.

I also get the please check the numbers thing to pair it. And when I don't, the hole thing gets disconnected and removed from my Bluetooth devices.

Will try to get the support when I am home... 

Oh no.  Yes, it does sound like the same issue.  No offense intended, just making sure we were all having the same issue.  

I'm sorry you're having this issue.  I absolutely love my Garmin, I moved from another brand, beginning with F, that I'd used for years, but when the data started going behind a paywall, I tried Garmin.  Boy do I love the amount of data!  I don't know if this is your first Garmin, but if it is...stick with it.  Their customer service is really great.  My old VA3 had an issue where one of the lugs broke and even out of warranty period they sent me another.  

After i reset the watch, i did the update via wifi, as well as tried Garmin Express on PC to try to run update, that did not change a thing for me.