wrong fuse is pulled. or someone has bypassed it.
That fuse disables the headlight reminder and the dome light(to where it works w/ dimmer switch only)
I'm not sure why anyone would bypass it, so maybe it was unintentional, I'm not sure....but this seems like the most likely cause in my simple brain. Unless of course you pulled the wrong fuse.
Might take a look at the door sensors...since one of them is telling the light that it needs to be on...it should turn off after ~10 mins regardless - to avoid draining battery.