"Subscription pending" and all comments on posts in community on another instance not showing up

sh.itjust.works Book Collecting - sh.itjust.works

Community for discussing book collecting Rules: No bigotry: Including racism, sexism, homophobia, transphobia, or xenophobia. Be respectful. Everyone should feel welcome here. No NSFW content. No Ads / Spamming. Be thoughtful and helpful.

I wanted to subscribe to https://sh.itjust.works/c/bookcollecting@lemmy.world, but it just says "Subscription pending", and while I can post there and it shows all of the posts in the community, it doesn't show any comments to those posts.

If I visit the community directly through lemmy.world (without being logged in to an account of course), it shows that there are multiple comments to all of the posts, but if I visit through my account on this instance it shows 0 comments to all of the posts.

I don't know if it is connected to the "subscription pending" issue, but I have tried refreshing to make the subscription pending change into subscribed, but it doesn't happen.

Edit: I just tried posting in the community in the vain hope of establishing a connection to it from here, but when I press the post button it just continously loads while the error message "SyntaxError: JSON.parse: unexpected character at line 1 column 1 of the JSON data" keeps popping up in the corner.