Batteries load and unload at full power

My installation:

AND multiplus II GX 5000

3 Dyness B3 batterijset s

ET112 netmet er

5000W solar panels connected to the fuse b ox.

I have installed a new and larger fuse box. The ET112 is next to the main switch as prescribed and the RS485 to USB goes to th e GX.

everything was the same connected in the old fus e box.

The problem now is that when the batteries start to discharge, they do so at full power. I have the impression that the excess power is sent to the grid. The batteries are therefore empty after 4 hours (20%). Even when they start charging, it is at full power and they take power from the grid instead of using the surplus from the solar panels.

How do I fix this?