Yeah, I had almost the same issue. I contacted Wattpad Support, and they told me to make sure all the newly required story details were filled in, like Story Type, Genre, and tags.
In my case, the problem was the new Story Type update. Since my story is fanfiction, I had to add a fandom. There's a little green "New" label under the Story Type section. My fandom didn't exist yet, so I created one using the name of the novel my fanfiction is based on. After that, my chapters published normally.
It also lets you add multiple fandoms, but I only added one primary fandom and left the rest blank. That was enough to fix the issue for me.
Maybe check if your story is missing any of those new fields. Hopefully it's the same problem and an easy fix.
