Row level security error in Power BI with Tabular Model

I've a problem with row level security in a Tabular Model. This is the error:

I've a very big Tabular Model with some Roles. One of this Role, let's call it "Role01", is necessary to hide some information, depending of who access to the model. So I've this DAX query applied to a table "tableA":

'tableA'[ide cli]=LOOKUPVALUE('RLS table'[IDE_CLI], 'RLS table'[DEN_EMAIL], USERNAME(), 'RLS table'[IDE_CLI], 'tableA'[ide cli])

this DAX query filter 'tableA' depending on the 'E-mail' values in 'RLS table' when the DEN_EMAIL = USERNAME(). 'RLS table' is a calculated table created by a NATURALINNERJOIN between other 2 tables in my Model.

this is the xmla partition code for the 'RLS table':

"partitions": [
    {
      "name": "CalculatedTable 1",
      "source": {
        "type": "calculated",
        "expression": [
          "NATURALINNERJOIN ( ",
          "\tSELECTCOLUMNS (",
          "        TABLE_01,",
          "\t\t\"DEN_EMAIL\",TABLE_01[DEN_EMAIL],",
          "        \"IDE\", TABLE_01[IDE]+0",
          "\t\t    )",
          "\t,SELECTCOLUMNS (",
          "        TABLE_02,",
          "\t\t\"IDE_CLI\", TABLE_02[Ide cli],",
          "\t\t\"IDE_AGENT\", TABLE_02[Ide age],",
          "\t\t\"DAT_FINE_VALID\", TABLE_02[Date],",
          "        \"IDE\", TABLE_02[Ide]+0",
          "    )",
          "\t) ",
          ""
        ]
      }
    }
  ]

My problem is this error does not always happen but seems to be random. From the tests carried out it seems to happen during the processing of the model.

Can anyone tell me what the problem might be?

Thanks