JSS not loading properly

I’m currently working on a Jira App (made with atlassian’s node kit) that uses React for the Front-end with the Material UI library. I have previously tried to make a simple react page to see whether using React is a good idea and it worked.
So I continued and made a simple page with material-ui components, with some simple styling.
When the page loads on my Jira development site though the styling created using material’s styling options isnt properly loading. Does anybody have any idea how to tackle this?