Sounds like you turned off the specific language that the community users or, we haven't federated with that community yet! It sounds more likely that we haven't federated yet so let's check that.
If you go to Search (on reddthat web interface) and type in: [[email protected]](/c/[email protected])
that triggers the search/federation.
It should then show up and you should be able to subscribe. It will then start pulling in all the posts (so you might only see a few immediately).
If it's a language problem then you can fix that in your account settings. (As if you don't have a language selected it will not show any posts with that language).