Hi @kbb
The cause of this is your lithium battery BMS not complying with the Victron BMS-can specification.
Compatible batteries are listed here - Battery Compatibility [Victron Energy]
Further details why
The specification requires that BMS use the Charge Voltage Limit (CVL) not the Charge Current Limit (CCL) to regulate the flow of power to the battery.
When the CCL=0 value is set, the chargers take that as a signal to immediately cut their production to zero. Not try to balance the export current vs battery charging current.
That balancing of export vs battery charging is much better done as a battery voltage target, not a current target, because current is so fickle between loads, clouds, etc.
The BMS-Can specification isn’t open source, but it is freely available from Victron to BMS and lithium battery manufacturers who want to improve compatibility with Victron. They can get in touch with the Victron sales manager in their region to make the request for the information to bring their products into compliance.