Sc_set_theme doesn't work

My version is 9.10.0023
I use sc_set_theme( $tema ); ($tema is select set_value from sec_settings where set_name=“theme”)
Always, i try with sc_set_theme( “scriptcase__NM__Sc9_Lemon” );
Also sc_set_theme( “Sc9_Lemon” );

My grid application is set with SC8_Valencia, and this is the theme used … always

Does this macro really work ?