wrong pulse. drops in body battery

My watch does not take my pulse accurate at all. yoga modus is better but still far away 50% if the times. 64 when it was over 150. standing still. my body battery falls over a cliff almost every day. charged +60, then some minutes later +119, one minute later +152. had it for half a year now and need to have a belt connected if it’s gonna take my pulse. so i’m using it for incoming calls basically. i have cfe, pots and svt attacks so I both this experience thing to keep an eye on things. some tips? garmin 255 music

finally slept okay tonight. watch said i didn’t sleep.