SSRS parameters with combined members not working

Question

I've created a new report parameter. It seems to work in the parameter query, and I have all the desired members in my drill-down parameter list. But, when I try to see my report in preview mode I do not have all the data: the data regarding both of the new member ([DEEM] and [Autres]) are missing.

Any help? I'm a biginner in MDX and SSRS. Here my code:

    WITH MEMBER [Measures].[ParameterCaption] AS 
[Etudes].[Niveau].CURRENTMEMBER.MEMBER_CAPTION 

MEMBER [Measures].[ParameterValue] AS 
[Etudes].[Niveau].CURRENTMEMBER.UNIQUENAME 

MEMBER [Measures].[ParameterLevel] AS 
[Etudes].[Niveau].CURRENTMEMBER.LEVEL.ORDINAL 


SET [DEEMaggregate] AS
     
        {
        [Etudes].[Niveau].&[DAES II]
,[Etudes].[Niveau].&[DEEM]}

MEMBER [Etudes].[Niveau].[Deem] AS Aggregate([DEEMaggregate])



SET [combined2] AS
    
{
[Etudes].[Niveau].&[Autres diplômes]
,[Etudes].[Niveau].&[Formation complémentaire]

,[Etudes].[Niveau].&[Licence-diplôme]
,[Etudes].[Niveau].&[Post-doctorat]
,[Etudes].[Niveau].&[Préalable DAES II]
,[Etudes].[Niveau].&[Préalable DEEM]
,[Etudes].[Niveau].&[Préalable doctorat]
,[Etudes].[Niveau].&[Préalable master]

        }
        
MEMBER [Etudes].[Niveau].[Autres] AS Aggregate([combined2])

SELECT 
{
[Measures].[ParameterCaption],
[Measures].[ParameterValue], 
[Measures].[ParameterLevel]

} 
ON COLUMNS,
 
 Union(
        Except([Etudes].[Niveau].[Niveau].ALLMEMBERS, {[Etudes].[Niveau].[All],
        [Etudes].[Niveau].&[N/A],[DEEMaggregate], [combined2]}),
        {[Etudes].[Niveau].[Deem] , [Etudes].[Niveau].[Autres]}
    )
            
ON ROWS

FROM [my cube]```