OnValidate event failed.

[rcloayza]

I have several persistent fields in TpfIBDataset.
In some of them I incorporated validations using OnValidation.
When this event is triggered, the entered value is replaced by the value of another field without any explanation.

procedure TfrmAreasPrincipal.ParamsimDENSValidate(Sender: TField);
begin
//Sender.Value=> 1250
//ParamSimEDAD_I.Value=>5
//ParamSimID_ZON.AsInteger=>1

   If (ParamSimEDAD_I.Value=0) Then
       Exit;
   //Sender does not intervene here In SetRange
   SetRanges(ParamSimID_ZON.AsInteger, ParamSimEDAD_I.AsInteger);

   //After SetRanges change value to Sender.Value

  //Sender.Value                         => Set value to 5 ERROR!!!
  //ParamSimEDAD_I.Value        =>5
  //ParamSimID_ZON.AsInteger=>1

  if Sender.AsFloat<1000 then
    raise exception.create('Error value');

end;
Does anyone know what could be happening and how to correct this anomaly?

Delphi 10.2
thank you
Christian Loayza