Wavy glissando not working on harp

For some reason, when I try to put in a glissando for the harp in my score, if I use the wavy glissando, all the notes pile up at the end instead of being a gradual shift. But, if I use the straight glissando, it works like how I intended it to. I'm not sure if it is a glitch/bug or if it is how it is supposed to sound, so any input on the situation from someone with more musical knowledge than me would be helpful.