I already posted this in the Vivoactive subforum, but I think this is mainly related to the Garmin Connect mobile app and might affect other watches too.
I have a new Vivoactive, updated to latest firmware 3.2 and I also have the latest Android version of Garmin Connect app for my Samsung S6 device (2.13.2.1).
If the phone is connected to wifi/data there are no issues getting notifications on the watch. However if the phone is not connected to data anymore and the watch loses connection to phone (by going out of range for example) and then reconnects, the notifications aren't received anymore (the widget shows "waiting for data"). I think this happens anytime the watch connects to the phone and the phone is offline.
All other widgets, such as weather or music control, are working fine.
I think this is a bug as the watch should still be able to get notifications (for calls/texts) even if the phone is not connected to wifi/data. And I think this might be an issue with the mobile Android app itself (someone mentioned they do not encounter this problem on IPhone).
I hope the developers see this and find a way to fix it, as the watch should be able to get to notifications anytime it is connected to the phone.