I have noticed this couple of times, I can’t reply to users from kbin.social. The loader keeps spinning, and if you refresh, the reply doesn’t show.
Is this a known issue, or just some random network / system load issue?
Solution (also posted as a comment below) Select ‘English’ as the language for the reply, otherwise it won’t post to any instance that doesn’t have ‘undetermined’ in the languages or to kbin.social account.
The communication would only be between the two servers involved - the fediverse as such is fine. But the sites of the “threadiverse” are indeed a bit overloaded. ;)