How do i change my ndsl setting?

i just found out that my ndsl theme change ';automatic'; after i chargd my ndsl. then i realized my time and date is also wrong!?



i tried to find out how to change my settings however i could not locate any setting menu in my ndsl...i've read several post and tried some troubleshooting however it doesnt works!



is anyone encounter de same problem as mine??any solution?How do i change my ndsl setting?
and somebody told me dat the theme change according to the month..

1 month 1 theme..total 12themes i can hold in my memory card..



but then...how to change my theme? i read some post regarding the theme can be change by pressing ';select'; but it is not working with my nds...