it could be that you have to blow out the the dust in your nds gba slot or EZ 3-in-1 expansion. It could also be that it's not inserted fully or properly in your nds. Or else i really don't know because i also ordered one from DX and i have yet to try to use it
Tell them to get the DSTT cause you can get it for less than $10. And my friends never listen to my recommendations even though i recommended them the Cyclo and other good carts