With the latest updates, rounds will only be posted to the feed if you tap Post in the end. If you choose Skip, then the round will be saved but not shared on your feed.
That's the reason why your rounds are not appearing on the feed screen, but are correctly saved on your Rounds list tab. Please check here how to view your saved rounds on iOS or here for Android.
This might be a big change but it's also one of the biggest requests from our golfers.
You can always share your rounds later to the Hole19 feed, Facebook or Twitter. See how to do it here for iOS or here for Android.