Thanks for the reply - very interesting. The issue for me only started happening about 12 months ago - before that it was fine, no issues displaying all data - including heart rate data. As you say, all heart rate data is displayed on the Zepp iPhone app - so it seems that the issue relates to the Zepp / Strava connection, rather than a Amazfit issue.
I've looked at my Strava settings and there's nothing obvious that jumps out as being problematic. I think it may be connected with Strava and the heart rate / health data settings on the phone? Thoughts?
I also thought it was Strava, but it can’t be. Like I said, I recently signed up with intervals.icu, and I configured it to pull data directly from my Amazfit account. As the attached image shows, the last quarter of my pace, heart rate, and cadence data is a flat line. Just like in Strava. So the problem is not with Strava, since the same thing happens on both Strava and intervals.icu.
Also, I went back and checked and you were right. My full heart data was sent to Strava on August 11, 2025…but the last quarter was missing for the activity on August 14, 2025. So Amazfit must have made an update to their software in early August 2025 that broke the data transfer to other apps.
