NEWBIE - Please Help

guys please help, i feel like i’m losing my mind lol. i’m so close to finishing my project but i can’t figure out why my lines are looking like this on design space?? they are perfectly smooth in illustrator but as soon as i upload it into design space, they get all ugly and jagged like this and i don’t know how to fix it. i tried messing around with color tolerance and reduce color but it hasn’t helped. it’s such a simple design, i don’t understand. does anyone know what’s going on??