Why are my pencil lines filling in when the fill is off


Hey, hoping someone can help 🙂
I'm manipulating font and I've added a few pencil lines coming off the letters. The stroke is black and the fill is off. When I go to unite the lines & letters to make one shape, the pencil lines fills themselves in & change the fill to black, when I need the letters to be filled but the pencil lines to stay stroke only
Even when I don't try to unite them and just try to change the colour, the pencil line's get filled in. I don't understand why this is happening and am unsure how to get it to stop, I want the lines to stay looking the same. Someone help!
