Update:
So it looks like the issue is with card.js in the <Link> component. The as part seems to be the bit confusing Next before it loads it in:
<Link as={`/article/${article.slug}`} href="/article/[id]">
I’ve removed the as and changed href to: <Link href={`/article/${article.slug}`}> and that seems to work now! But now my question is…why use as in the first place? And when using as why does href have [id]? There is no [id].js file anywhere, just [slug].js so I’m a bit confused. Any help would be very appreciated!
Thanks