The ECG app isn't detecting my fingers

The ECG app isn't detecting my fingers

I've successfully activated the ECG app and taken readings, specifically on June 15 and 16. They've been registered correctly on Garmin Connect. However, for a few days now, the watch hasn't detected my fingers when I place them on the watch face.
I've tried deleting the watch from Garmin Connect and reconfiguring the ECG app following the steps indicated, but it's still the same. It doesn't detect my fingers. I've noticed that it also doesn't activate the sensor under the watch when I'm in the ECG app. Once I exit the app, everything works normally, and everything else is fine.

Can anyone tell me what's going on? I've attached a video of the problem.

https://www.reddit.com/r/Garmin/comments/1lsxp3c/the_ecg_app_isnt_detecting_my_fingers/