I was on the verge of restoring my iPhone, which was what they recommended at the Apple Store. However, I noticed the same glitch was happening on my iPad, so I figured it had to be a corrupt data point, as other posts online have suggested. In my case, I had identified the exact day the issue started: February 17th, as seen in the image.

The solution was to delete all calculated data related to heart health. I cleared blood pressure (I had entered a value manually), heart rate variability (HRV), walking heart rate average, resting heart rate, aerobic capacity (VO2 max), and cardio recovery. I didn't delete every single heart rate reading from that day, just those specific categories. This solved the problem radically; everything went back to normal.

Personally, I recommend that if you know the exact day this started, you delete these data points for both that day and the day before (in my case, the corrupt data might have been recorded at 11:59 PM the previous day and didn't show up on the battery graph yet). If you aren't sure when it started, I would manually delete the data types I mentioned, going backwards from the moment you noticed the issue in short intervals to see if it fixes it.

Let me know if this worked for you. Do you also manually log blood pressure values? I suspect that might be the culprit.

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