Bad control behaviour of VICTRON ESS Multiplus2-5000/CerboGX

Hi Community. I have the system described above. Unfortunately, the power flow to the grid varies greatly. If I have a larger load of around 1,5kw the power flow goes always up and down from about 2kw to some Watts. Is there no way to set a PID behavior for the Cerbo GX? I’m a bit frustrated.
The system also draws a relatively large amount of energy from the grid with the load

Is there another way to improve the rule properties?

Many thanks for your help

The VICTRON Cerbo GX controls right. Parameters I send on MODBUS TCP caused the problem