Wrong total Matrix / DistinctCount measure

Hello,

I have a problem, I want to count the numéro of unique value of an Customer, by using ID_Customer :

CALCULATE (DISTINCTCOUNTNOBLANK(ID_Customer)

)

and use an field for dispatch the value on 3 group on column.

The field used for group the value is created on the data model at column level, by using a SWITCH function, for exemple :

SWITCH (TRUE(),

Code_BU = "N", "National",

Code_BU = 9, "Départemental"

ELSE "Others"

)

The total of the column of the Matrix are wrong, it not corresponding.

Please could you help me to correct it ?

Kind regards.