cannot hide a column (nested grid)

I’ve a grid with a nested grid in a column.
A few months ago I could hide this colum through field button on the application
Now, this field is grey and when I drag and drop, it returns to the righ side (visible fields area)

any idea?

thanks

Hi
is there a way to hide a column with a nested grid, like you are able with any other column when you want via “Columns” button

thanks.