Body Battery Inconsistent

So today I did an easy run -- 46 minutes, base run, 3.0 Aerobic/2.1 anaerobic, load 118, average HR 150. Body Battery impact -2.

Then in the afternoon, I did a strength workout -- 41 minutes, base, 0.5 aerobic/0 anaerobic, load 7, average HR 98. Body Battery impact -17.

How does that make any sense? The body batter rarely recharges and doesn't match how I'm feeling most of the time, but this is ridiculous. Increasingly, I find I can't use features of the watch bc they aren't reliable.

I looked up yesterday's run --- my long run, 2h35, base, 3.6 aerobic/0 anaerobic, load 143, average HR 144 and it only dropped my body battery by 7. 

This watch tracks naps I'm not taking almost daily.

If I leave the watch on the counter overnight, it will recharge to 66, but otherwise rarely over 55 and never over 60. (But if I switch to my previous FR55, my body battery will recharge into the high80/low 90s consistently, my stress will drop immediately 20-25 points and heart rate by 12-15 points. I use an external HRM for all runs and weight activities.)'

Anyone else having problems with their 265 having a life of its own that doesn't match reality? 

ETA: watch has all current updates.