Settings -> ESS -> Grid Set-point. If you set the set-point to negative, then you allow discharging from battery to grid (i.e. feed-in from battery charge). If you set it to negative, then you allow charging the battery from the grid (i.e. draw for battery charge).
However, if you have set the "Grid metering" setting to "External grid meter" without having a valid external meter device added to the system, then the battery will never charge from the grid even if you set a positive grid setpoint.
That option in the menu should be disabled if no external grid meter device exists in the system.
Settings -> ESS -> Grid Set-point. If you set the set-point to negative, then you allow discharging from battery to grid (i.e. feed-in from battery charge). If you set it to negative, then you allow charging the battery from the grid (i.e. draw for battery charge).
However, if you have set the "Grid metering" setting to "External grid meter" without having a valid external meter device added to the system, then the battery will never charge from the grid even if you set a positive grid setpoint.
That option in the menu should be disabled if no external grid meter device exists in the system.