I have brought this up before to the dev team, and asked for a simple setting to only calculate RHR during waking hours. I've been told that it's being "considered".
BenBristol, do you have sleep and wake times as the same?
I got the same issue, we all got it, well except those fun boys that carry the master name, they are all trolls and their watch have no flaws.
. I like the watch but it has many bugs, the only way these dudes at garmin are gonna fix it is thru complaining about their horrible bugs.
same issue still happening in 7.0 Beta, it seems they will never fix this.
Just make your sleep time = wake time per my previous post and issue solved.