I think the error was with Steem and not Hive. So in both cases the post went through but did not post on Steem.
Hive is a hard fork of Steem, accounts that were on Steem migrated to Hive (like a copy 1-to-1) but users that did a Hive account after the fork probably do not have a Steem account, that may be where the issue is (I'm always assuming so I might be wrong 😅)