Yes, I'm having the same problem with my Garmin Vivofit and Vivofit 3. Android did a system update to N910VVRU2CQF2 on 8/8 and ever since I can't connect either of my Vivofit fitness trackers via bluetooth on my Samsung Note 4. The tracker is fine since it can still connect to my Samsung tablet. I have been talking to Garmin and Verizon. I have done the following:
uninstalled and reinstalled the Garmin Connect app
removed and tried to re-add my devices (it says it can't communicate with my trackers)
taken the phone down and brought it completely back up
factory reset the Garmin Vivofit
tried to add the brand new Garmin Vivofit 3
worked with Verizon and reset my connections
Nothing is working. This is frustrating.