Heart Rate zones keep resetting to %Max

Hey all,

Since couple of weeks my Garmin is bugged. My heart rate zones keep resetting automatically to %Max Heart rate while I set them to custom.

Yes, I updated the firmware to 29.22.

Yes, I disabled everything auto-detection related stuff. Sometimes it resets after a sync with Garmin Connect. Sometimes it doesn't. 
Im also using a datafield to see which Heat Rate zone Im in and last time it remained in zone 1 while I was in all zones across the boards. The data field refused to work.
Power still works, though. I vaguely remember this issue with power as well until it got fixed somewhere.

Any tips?