MiBand - heart rate graph is missing - Sleep as Android

Check your HR settings in the Mi Fit app.

When the Mi Band is in Sleep Assistant HR mode in Mi Fit, it doesn’t feed the HR data to Mi Band Tools / Sleep as Android. When it is in regular HR tracking mode (24-hour), it works.

This is a companion discussion topic for the original entry at https://docs.sleep.urbandroid.org//faqs/miband_hr.html