Keyfigure Dimension selections are invalid!

Hi All

I am still getting to know Design Studio

I have a Task to create Desktop Application in DesignStudio.

I have already done this but one area i am currently facing challenges is

in my Listbox which is to give  3 Keyfigures selection options.

I have populated the Listbox with techname and descrptn. of the keyfigures as known in Infocubes query and wrote the script below

DS_1.setFilterExt("0MPR671LHGYJO9LOPL3CLPFM4", LISTBOX_1.getSelectedValue());

DS_2.setFilterExt("0MPR671LHGYJO9LOPL3CLPFM4", LISTBOX_1.getSelectedValue());

DS_3.setFilterExt("0MPR671LHGYJO9LOPL3CLPFM4", LISTBOX_1.getSelectedValue());

DS_4.setFilterExt("0MPR671LHGYJO9LOPL3CLPFM4", LISTBOX_1.getSelectedValue());

to retieve and filter selected Keyfigure, but i keep getting this error message below.

The query from query designer is working quite well when tested.

"All selections for dimension Key Figures are invalid and have been discarded"

I will appreciate any tip on how to resolve this issue.

Thanks