Hallo @goliat0815 , schön dich kennenzulernen!
The Victron display is merely relaying the alarm that was sent by the battery on the CAN-bus. Ideally you should run BatteryView while the battery is in this condition, and look for a low cell. I don’t know what Pylontech considers a low cell, but I would expect a value below 2.9V or even below 2.8V.
I don’t think the Pylontech people actually read this forum actively, I suspect one of their employees visited a few times just to warn people about installing just any old firmware they find on the internet.