jvmagic

Hi,
my 2010 is250 use to sound off a chime
when my front passenger would not put
their seatbelt on.
All of a sudden that is no longer the case. If they don't wear their seatbelt, no sound goes off.
I know most don't care for it but I want this to be an option.
How did it just magically disappear?
thanks in advance