SAP connector schema extension in One Identity version 8.1

Hello!

I expanded the SAP connector schema. An example of a schema: 

<?xml version="1.0" encoding="utf-8" ?>
<SAP>

    <Functions>
        <Function Definition = "HRP1001 SET" FunctionName="Z_OM_IDM_INS001_RFC" OutStructure = "" Key ="SOBID,OBJID,BEGDA,ENDDA" X500 ="CN,OU,OU,OU">
            <Mapping>
                <Data ParameterName = "SOBID" PropertyName = "SOBID" />
                <Data ParameterName = "OBJID" PropertyName = "OBJID" />
            </Mapping>
        </Function>
        <Function Definition = "HRP1001 UPDATE" FunctionName="Z_OM_IDM_INS001_RFC" OutStructure = "" Key ="SOBID,OBJID,BEGDA,ENDDA" X500 ="CN,OU,OU,OU">
            <Mapping>
                <Data ParameterName = "SOBID" PropertyName = "SOBID" />
                <Data ParameterName = "OBJID" PropertyName = "OBJID" />
                <Data ParameterName = "BEGDA" PropertyName = "BEGDA" />
                <Data ParameterName = "ENDDA" PropertyName = "ENDDA" />
            </Mapping>
        </Function>
        <Function Definition = "HRP1001 DEL" FunctionName="Z_OM_IDM_DELETE1001_RFC" OutStructure = "" Key ="SOBID,OBJID" X500 ="CN,OU">
            <Mapping>
                <Data ParameterName = "SOBID" PropertyName = "SOBID" />
                <Data ParameterName = "OBJID" PropertyName = "OBJID" />
            </Mapping>
        </Function>
    </Functions>
    <Tables>
        <table Definition = "HRP1001-Table" TableName="HRP1001" Key="SOBID,OBJID" X500="CN,OU" SQL="MANDT = sy-mandt AND RSIGN = 'B' AND RELAT = 'Z01'" Load="BEGDA,ENDDA"  />
    </Tables>
    <SAPExtendedSchematypes>
            <SAPExtendedSchematype Bem = "SP, HRP1001" Name = "ZZZ_HRP1001" DisplayPattern="%SOBID% %OBJID% %BEGDA% %ENDDA%" RevisionProperty=""
            ListObjectsDefinition = "HRP1001-Table"  ReadObjectDefinition = "HRP1001-Table" InsertObjectDefinition = "HRP1001 SET" WriteObjectDefinition = "HRP1001 UPDATE" DeleteObjectDefinition = "HRP1001 DEL" />   
    </SAPExtendedSchematypes>
</SAP>

Inserting and deleting objects works without problems, but when trying to change (update) an object, an error occurs:

[1777007] Error committing 1 system objects.
    at VI.FormBase.UILogic.TriggeredExecution._EventHandler(Object sender, EventArgs e)
    at VI.Projector.UI.Controls.ObjectBrowserControl._SaveCurrentObject()
    at VI.Projector.Connection.SystemConnection.CommitObject(IEnumerable`1 systemObjects, CommitObjectOptions option)
Objects of type table are intentionally read only.

What am I doing wrong? One Identity version  8.1.