Unable to delete dimension members

Hi,

I cannot delete Dimension members anymore even if they are not in an hierarchy or carry data.

When I click the "Delete" button in the web UI the member disappears but after a "Save and Process" it's back ....

I've found already some posts where user recommend to Change a property first and delete afterwards. Or where I should use the Report UJA_REFRESH_DIM_CACHE .... Anyway I had no luck

BPC 10.1 NW SP 6

Thanks