Hi Hubert,
The issue here is with the connector itself. We were also facing the issue, and upon checking with the sailpoint and connector team, we have been told the Function module configuration for this connector has been decomissioned from RFC_Read_Table to /SAILPOIN/SAIL_READ_TABLE_LEG, which sap team needs to implement at their end. Post updating the module, the issue is fixed. Please go through the below link and see for more information