Advance filter/sort form cannot save sorting

Hello,

I am using AX2009.

We have a problem on advance filter/sort form.

In AX form, e.g. Quarantine Order, Advance filter/sort, we add N:1 relation table, then go to tab “sorting”, add field on it, define the direction, then Click “Modify” → SAVE, then the sorting tab is automatically Emtpy.

Do you know any reason for this problem?