Hello Juergen, the Support wil lonly help if it is under guearantee. The fact that this is a 5+ year Lock dont mean anything because the issue appeared after a Firmware upgrade and was not there initialy.
It looks clearly like a memory leak as a RCA that the Battery is drained.
In my constellation over the years nothing has changed except the Firmwares.
As Support will not help here in the case, I also asked if there is a way to rollback the firmware to the former version.
Is this feasible ?