Hand Tracking not Working on Quest 1

Hi all, I've been working on an app for Oculus Quest 1 (Unity, Integration SDK), using Link.

Until today everything was working fine. Suddenly, all of the scenes using hand tracking (through the Interaction SDK) have the following problem: the hands are not showing.

In the Oculus Home (with hand tracking) everything is fine. I tried to enable/disable hand tracking, restart the device.

I tested on three different Quest 1 but the result is the same.

I changed literally nothing. What could have happened?