inreach mini deplete battery when off

purchased my Garmin inreach mini last November (2019) and found it to deplete battery completely when powered off within several weeks.

I've been in contact directly with Garmin support (case id:  16371714K1) for several months which didn't solve anything

I've upgraded the firmware, reset to factory default as they asked and it still happening.

I've lost completely my faith in Garmin and wasted 300$ on an expensive paperweight :(

definitely won't rely on it when going out to the wild.