UltraGrid keeps showing Hidden columns

There is this particular UltraGrid that is supposed to show 2 out of 4 columns in a DataTable, but despite labelling them as Hidden, those columns that should not be displayed still come out visible. I am for now not able to determine what is the difference between this grid and the rest of the UltraGrids in other forms that do hide their columns as instructed.

Besides setting the Hidden property to True in the UltraGridColumn, is there something else I missed? The Keys are correctly defined to the column names.

I have destroyed the UltraGrid control in the designer and placed a new one in, only to face the result irritating result. In the end, I found that those Hidden columns were somehow being reset back to False by something somewhere. I had to insert explicit reverting code to counter this

    this.checklistGrid.DisplayLayout.Bands[0].Columns[2].Hidden = true;
    this.checklistGrid.DisplayLayout.Bands[0].Columns[3].Hidden = true;