Auto sleep tracking ignore the smart band

Hi there,

I recently bought a new smart wrist band and paired it with my Sleep as Android. When I manually launch the sleep tracking everything works fluently with no issues. However, when I forget to start it before falling a sleep, and it kicks off automatically, the sleep tracking avoid connecting the band.

Weirdly do, in the last two nights the tracking started automatically and in both cases it’s just stopped with no reason at exactly the same time - 5:11 AM. Something is going on here and I just don’t get it.

And even more important to me, why I can’t use my band when the tracking is automatically inaugurated?

My band: Amazfit band 5
My phone: Xioami Mi A3
My Android: 11