Android: power2max bluetooth disconnects after 90 mins

Hi All,

Have a strange problem, generally well-working setup of Samsung S6 Galaxy Tablet connecting to power2max NG power meter over bluetooth. Connection is stable and readings are reliable… until power drops to zero about 90 minutes into the ride. Problem observed very consistently on 3 out of 3 last long rides.

Trying to reconnect in zwift menu restores readings for a minute or two, then drops back to zero.
Restarting power meter (battery removed / reinserted) does not change anything. Restarting zwift app solves the problem, but not really a sustained solution - kicks me out from long organized rides.

Please help!

One additional detail, power meter is in parallel connected to Garmin watch over ANT+.

Thanks all,