Primal is a platform, but not a "real time" client. It does copious caching for performance and network improvememts, but delayed so users who are viewing a feed may not see your responses at that time if you posted with a different nostr client.
It doesn't seem to be this problem. It hasn't been for many days. The replies under the main post are not displayed. They recently changed the way the reply event is handled. Because it exists in the reply area of ​​the personal homepage. But clicking it does not enter the thread of the main post.