Numerals not showing

Hey there, a friend of mine is running Side Matter on two of his sites. On one of them, though, the numerals aren’t showing up – instead, it looks like they’re being replaced with a thin line above:

https://www.culturemaven.com/blog/2015/06/17/daily-chronicle-culture-maven-goes-paperless/

any help you could give would be appreciated. Thanks!

https://www.ads-software.com/plugins/side-matter/